Author Topic: Preventative measures for a 6.2L IDI detroit  (Read 8701 times)

Offline MuddiGGEr25

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Preventative measures for a 6.2L IDI detroit
« on: December 27, 2016, 02:00:00 AM »
I am very sorry for the long winded explanation, as usual just trying to cover my bases so i dont have to answer simple questions.

Ok so, ive been doing alot of research and i mean ALOT, i literally read over 200 pages about various vehicles with the 6.2L, C-Code and J-code differences, gear ratio and MPG with each one, 6.2 in 5/4 Military truck, fritolay vans, RV's(most of which apparently failed miserably) 1ton duallys and in K5/K10 blazers.

I understand they were designed as a light duty short stroke diesel, which is fine, im not intending to idle it excessively or pull beyond its rated 8,500lb towing capacity.


The previous owners moved up from california with this burb in 2008/9 made the drive from southern CA to central ND not once but 2 times, the first trip was hauling one of those double axle uhauls around 5Klbs with 3 kids, 2 dogs and his wife + whatever they could pack in the very back, so im gonna guess pretty dang close to the 8,600GVWR +5,000lbs, he claimed it got around 14-16mpg if he stayed under 55mph, the second trip they drove back to CA and grabbed the travel trailer, i saw a pic of it hitched up and he said it was 28ft IIRC, a mid 90's tandem axle model so probably weighed 5K-7K depending on how much stuff they threw in it, and a WD hitch, so they have pushed the limits of the this truck for GCW in the 15K range already and claimed if driven moderately (he has 3 sons with autism so any other way would bother them very much, i know as i have 2 autisic brothers, and i have been diagnosed along time ago with aspergers) it  can pull off 14MPG while towing.


I already flat towed my other burban (cliffy) back at 55-60mph a total of 160 miles, he only weighed about 6,000 that day, and the blue burb was fairly empty as well, so i would guess combined i was only 12K at the very most, it had plenty of power to pull it all up except the most steep grades 3%+ and i would bog down to around 40MPH but once at the top i would regain to 55 easily.  The fuel was still from 2009 when it was parked, and i added diesel 911, powerKLEEN, and howes ( maybe overkill but i wasnt taking chances), i got a water in fuel light a few times, and the battery died killing the engine 2x because the alternator wasnt charging, the fuel tank was not completely full, a little above 3/4 ~ 24gallons, and i can say that i idled atleast 4 hours on that trip. and i had 2ish gallons in the tank when i arrived home, so 22 gallons for 160ish miles i got 7-8mpg, with 6 year old fuel that looked nasty.

I have been running lucas fuel injector cleaner(its good for diesel fuel too) and howes in every fillup, but i dont think im getting more than 15-16mpg highway empty, but i am running 65-70mph sometimes, and my vaccuum pump doesnt work anymore, i just recently got an electric vac pump so the TH400 shifts now, but getting a bigger one next month so i can try the cruise control too.

I seem to be getting 11-12mpg in town, while leaving it idling most of the time (just trying to run alot of cleaners through the injectors)

I lost the starter a month or so back, and the used one went bad about 2 weeks ago when it was -30F here in ND (no joke, that week it was actually warmer in antartica) anyway going to get another used one tomorrow, and planning out our honeymoon trip this week.

We will be going to either Colfax LA(April 25th) (1300 miles one way)  or Moultrie, GA (April 5th)(1600 miles one way), depending on when my season work wraps up and spring arrives, will dictate which event we head to.


I know hatzie will comment on here and advise all the braided german fuel lines (yes yes ive been listening lol)

I am 99.99999% sure its my fuel filter housing thats leaking down since i put a plug on the output and primed it and still lost prime after a few hours and the electric fuel pump i am currently using has a checkvalve.

I am taking a look at a 1984 34ft tandem axle trailer next week, he says its mostly all there, but the slideout is shot so he was going to make it a fancy icehouse but never got around to it, he was considering selling it for $50-$150 just to get it out of the yard if i help him take the A/C off the roof.  The inside should be about 6ft high inside (just tall enough for a grown man to stand up) and i know i can make cliffy just under 6'1" just by letting the current tires down to 10PSI, and removing the rear spoiler/flag mounts.

My current idea is to gut the rear 20ft of the camper, except for the walls, ceiling and floor, i have hauled many many campers and almost every single time they were wider than cliffy by a good margin, so it hopefully will be wide enough inside. I can also take off the drivers door or climb out the back if its a tight fit (its a mudding truck so thats no issue)
If cliffy wont fit inside, i always have the option of just cutting off the back 20ft of the camper, and make that portion a flatbed, and move the rear wall forward so it would still have a 12ft camper in the front for living/tool space.

The camper once gutted should weigh about 2K-3K, thats roughly what my buddies 30ft gutted icehouse weighed, but i know thats dependant on frame/axles, and weight of the walls and roof too.

I can roll it across the scales if i buy it and see for sure, i asked him for the make and model if he can make it out there tomorrow  (we got a major ice storm across the whole state on christmas day)

I should be able to get cliffy's weight down to 5K by removing the seats, leaving the fuel tank low before loading up, and taking everything out, i know with me in him and a load of tools, i roll across the scales at 6100lbs i can easily drop 280lbs for me, 50lbs for fuel, and probably 100lbs or so for the seats, and 100lbs for tools and other junk, or atleast im hoping.

The trailer would be weighing 7K-8K but i think the hitch and (old trailer house style) axles are only rated for 7.5K so i wouldnt want to push it.


So here is a list of everything I can think of for "preventative" upgrades before such a long trip:

Fuel lines, and clamps

Fuel pump and filter housing from 6.5L TD

LARGE Tranny cooler

Trans temp gauges, one as its leaving the trans and one as its leaving the cooler, the 2nd one just to monitor cooling efficiency

Possibly a set of exhaust temp gauges just to keep an eye on exhaust temps, but i dont intend on turning up the IP right now so that shouldn't be an issue.

Cold air intake or insulate the existing air tunnel and filter housing

Possibly a CS130D alternator for better output at idle, only for charging the deepcells on the camper when the solar is not keeping up

Synthetic Diff fluid in both axles, but im not sure if the G80 axle needs additive or not, i havent looked it up

I was looking into the 5w40 synthetic HD motor oil made my Mobil1, i have noticed lower temps and run my engines hard with Mobil1 and a quart of Lucas, so i was going to do an oil change with that.

Drain and fill the Tcase with syn also
(basically trying to reduce friction and resistance anywhere along the drivetrain)

I run 70% water and 30% antifreeze in my street racer, and in cliffy during the summer, and my last 2 RV's because i know that water transmits heat alot better than glycol or any glycerin, and i run my mud truck at 4000-6000RPM for hours, and towed hard with it and never had an overheat issue, so i would do that also.

I was also considering a Diff Temp guage for the rear axle.. i know its a 14SF and should be pretty sturdy but i guess better safe than sorry?

I would also refill the A/C system so i had AC on flat roads :D



..........................

I would think that would about cover it, the tires are only 7 years old, minimal weather cracking and i have a full set of roadworthy 10ply if i need extras.



I am fine with going 50-55mph on flat roads and slowing down to 25-40 on the hills, or even pulling over if my temps start to climb and let it cool off for a bit. Its not a race and its not the end of the world if it takes an extra 4 hours to get there lol.  I know a 350TBI, or 454 of any variety would have more torque, but this just comes down to the fact that business is alot slower than expected this winter and im not going to have the extra funds i thought i was. So im making due with what i have already. and i mean if i break the 6.2L then i will pull out cliffy,  winch the 6.2 into the back of the camper, and finish the trip with cliffy doing the towing, i mean i will have a spare EVERYTHING, except engine lol
1988 V10 Suburban 5.7L TBI/TH350 39K on rebuild 4.10AR GM14FF/GM10SF 235/85R16 & 18.4-16.1

1988 V20 Suburban 6.2L-J/TH400 CA truck, 125K G80 14FF/ GM10 4.10AR GVWR 8,600

1977 Ford Granada ~450HP 302 2bbl/C4 27K original 2.47 215/70R14

Offline hatzie

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #1 on: December 27, 2016, 04:42:58 AM »
Use Mobil 1 5W40 Turbo Diesel Truck oil in your 6.2.  It has quite a lot more Calcium (detergent) to keep the soot in suspension along with a lot more Zinc and Phosphorous anti-wear compounds in the add pack than the gasoline engine oils.  Shell Rotella T6 5W40 is another good one for the same reason.

-I'd look into LPD (Low Pressure Drop) plate coolers.  They self regulate temperature and are supposed to be between 30% & 50% more efficient than the tube and fin coolers.  The 28,000 GVW Tru Cool LPD4590 would work quite well. Completely bypass the radiator cooler.

-Don't bother with Synthetic ATF in the Transmission.  I run Dexron VI in the TH350, TH400, TH700R4, 4L80E, & 4L60.  ATF that meets Dexron VI will be an excellent shear stable oil and is backward compatible with Dexron II & Dexron III.  If the bottle says Dexron VI, not "Dexron Compatible", it's licensed and tested by GM so you know it meets spec.  The Supertech Dexron VI from Walmart is the same as any other ATF that says it is Dexron VI on the bottle and the price is right.  There has been no such thing as Dexron III licensed and tested by GM for a little over a decade.

-Install a Magnefine filter in the transmission fluid cooler return line and weld or braze a drain plug into the transmission pan.  Replace the strainer at the same time.  After that's done you can change the ATF just as easily as you change the engine oil.  As long as you replace the 25 micron Magnefine filter you will not need to change the 100 micron strainer again for a very long time as there will not be particles large enough to get caught in it.  There are counterfeit Chinese manufactured Magnefine filters that have some serious problems. There are several articles on how to identify counterfeit Magnefine filters and where to get the real Australian manufactured filters. Google it.   You should probably replace the magnefine at the same time as the engine oil at least two or three times to get rid of any crud floating around in the transmission and cooler lines but you shouldn't need to replace the ATF for around 25-30,000 miles or even more.

-The NP208 & NP241 used Dexron II ATF from the factory. Dexron III was backward compatible with Dexron II.  In the 2007 or so Dexron VI service bulletin GM states: "Any vehicle that previously required DEXRON®-III for a manual transmission or transfer case should now use P/N 88861800. This fluid is labeled Manual Transmission and Transfer Case Fluid."  You can buy GM 88861800 from Summit Racing for $6.75 a quart.   
-The slip yoke NP205 used Dexron II so you can use the same fluid as the NP208 & NP241. The Pre-1980 fixed yoke NP205 used 80W90 GL4 gear oil.  You can probably use 75W90 in the 1980 and before NP205 fixed yoke transfer case.

-The 10 bolt front axle will do just fine on Synthetic 75W90 GL5 Gear oil.

-The G80 Eaton Gov-Loc is a locker. Do not use Limited Slip additive.  You can use the slightly lighter 75W90 GL5 gear oil but I'd avoid Synthetics with the G80 locker.
-----------------------
LOCKING DIFFERENTIAL LUBRICANT (SERVICE INFORMATION) #91-4-109
SUBJECT: LOCKING DIFFERENTIAL (G80) LUBRICANT - (SERVICE INFORMATION)
VEHICLES AFFECTED: ALL LIGHT TRUCKS EQUIPPED WITH G80 REAR AXLE ALL YEARS
Some light duty trucks equipped with locking rear axles (G80) may exhibit rear axle chatter, especially when turning a corner from a stop.
This condition of alternate engagement and disengagement of clutches in differential assembly is usually caused by contaminated axle lubricant.
To correct this condition, drain and refill the rear axle with SAE 80W-90 GL5 (P/N 10950849).
The use of any additive in locking rear axles (G80) is not recommended. Rear axle additives are designed for use in limited slip differentials which are normally installed in cars. All light duty trucks equipped with RPO G80 make use of a locking differential and the use of additives will delay the engagement of the locking mechanism and may decrease axle life.
VEHICLES/COMPONENTS INVOLVED: --------------- Some light duty trucks equipped with locking rear axles, RPO G80.
SERVICE PARTS INFORMATION:
Part Number Description ----------- ------------------ 10950849 Lubricant, Rear Axle (1 litre)
Parts are currently available through CANSPO.
WARRANTY INFORMATION:
As specified in Light Duty Truck Maintenance Schedules, locking rear axle fluid drain and refill is required owner maintenance at the first engine oil change. Failure to drain and refill the rear axle as specified may contribute to a later axle chatter condition. Refer to the appropriate Light Duty Truck Maintenance Schedule or service manual, section OB, for further details on change intervals.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
© Copyright General Motors Corporation. All Rights Reserved
---------------
« Last Edit: December 27, 2016, 04:49:40 AM by hatzie »
SVC & wiring mans --> Here http://tinyurl.com/7387BRD-SVCMAN or My Bucket @ http://tinyurl.com/SQ-SVCMAN
Parts & Illustr Books -->http://tinyurl.com/SqParts
GMSTG Textbooks-->http://tinyurl.com/STG-TEXTBK
Radio Manuals-->http://tinyurl.com/DELCORADSVC

Offline MuddiGGEr25

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #2 on: December 27, 2016, 11:31:50 PM »
Use Mobil 1 5W40 Turbo Diesel Truck oil in your 6.2.  It has quite a lot more Calcium (detergent) to keep the soot in suspension along with a lot more Zinc and Phosphorous anti-wear compounds in the add pack than the gasoline engine oils.  Shell Rotella T6 5W40 is another good one for the same reason.

Yes thats the one i was referring to, not the 5w40 car oil, sorry i should have been more specific

-I'd look into LPD (Low Pressure Drop) plate coolers.  They self regulate temperature and are supposed to be between 30% & 50% more efficient than the tube and fin coolers.  The 28,000 GVW Tru Cool LPD4590 would work quite well. Completely bypass the radiator cooler.

I just looked up that LPD4590,I like that design, and its pretty compact, relatively speaking, the $100 price point isnt too bad either,  i know a generic 28K cooler would run me $40-$50 around here so for just 2x the price i can have a better design, thats not a bad deal at all..

Regarding the suggestion to bypass the radiator cooler, i very rarely do that, up north here, only because from november until march our actualy temperatures drop below zero, usually 10-30F below zero for days or weeks at a time, 3 winters ago we didnt see a day above 0F for about 2 weeks, and i would not feel comfortable driving around a 6K lb vehicle with fluid that is probably alot thicker than designed for.  I have bypassed the rad cooler on motorhomes, but they rarely if ever saw a road after the first flurries hit the ground so it was no issue, and they usually cooled betterbc the fluid isnt getting passed through 180-220F coolant. I also understand that it is potentially possible to have a internal Rad leak and fry the trans if coolant went into it and thats the reasoning behind alot of people bypassing them, but the PO "claimed" this rad was replaced at a shop in cali just a couple years before it was parked and when i drained it and inspected it, there was extremely minimal buildup, so at the very lease it had proper fluid in it.


-Don't bother with Synthetic ATF in the Transmission.  I run Dexron VI in the TH350, TH400, TH700R4, 4L80E, & 4L60.  ATF that meets Dexron VI will be an excellent shear stable oil and is backward compatible with Dexron II & Dexron III.  If the bottle says Dexron VI, not "Dexron Compatible", it's licensed and tested by GM so you know it meets spec.  The Supertech Dexron VI from Walmart is the same as any other ATF that says it is Dexron VI on the bottle and the price is right.  There has been no such thing as Dexron III licensed and tested by GM for a little over a decade.

Good info, i wasnt completely sure about the trans fluid, other than maybe topping it with a bottle of lucas trans additive, i can honestly say ive noticed a difference and its saved a few slipping trannies for me, atleast for a few thousands miles


-Install a Magnefine filter in the transmission fluid cooler return line and weld or braze a drain plug into the transmission pan.  Replace the strainer at the same time.  After that's done you can change the ATF just as easily as you change the engine oil.  As long as you replace the 25 micron Magnefine filter you will not need to change the 100 micron strainer again for a very long time as there will not be particles large enough to get caught in it.  There are counterfeit Chinese manufactured Magnefine filters that have some serious problems. There are several articles on how to identify counterfeit Magnefine filters and where to get the real Australian manufactured filters. Google it.   You should probably replace the magnefine at the same time as the engine oil at least two or three times to get rid of any crud floating around in the transmission and cooler lines but you shouldn't need to replace the ATF for around 25-30,000 miles or even more.

$16 for a filter that could save me tons of headaches in the future? heck yeah thats on my list now for all 4 vehicles lol

-The NP208 & NP241 used Dexron II ATF from the factory. Dexron III was backward compatible with Dexron II.  In the 2007 or so Dexron VI service bulletin GM states: "Any vehicle that previously required DEXRON®-III for a manual transmission or transfer case should now use P/N 88861800. This fluid is labeled Manual Transmission and Transfer Case Fluid."  You can buy GM 88861800 from Summit Racing for $6.75 a quart.   
-The slip yoke NP205 used Dexron II so you can use the same fluid as the NP208 & NP241. The Pre-1980 fixed yoke NP205 used 80W90 GL4 gear oil.  You can probably use 75W90 in the 1980 and before NP205 fixed yoke transfer case.

-The 10 bolt front axle will do just fine on Synthetic 75W90 GL5 Gear oil.

-The G80 Eaton Gov-Loc is a locker. Do not use Limited Slip additive.  You can use the slightly lighter 75W90 GL5 gear oil but I'd avoid Synthetics with the G80 locker.
-----------------------
LOCKING DIFFERENTIAL LUBRICANT (SERVICE INFORMATION) #91-4-109
SUBJECT: LOCKING DIFFERENTIAL (G80) LUBRICANT - (SERVICE INFORMATION)
VEHICLES AFFECTED: ALL LIGHT TRUCKS EQUIPPED WITH G80 REAR AXLE ALL YEARS
Some light duty trucks equipped with locking rear axles (G80) may exhibit rear axle chatter, especially when turning a corner from a stop.
This condition of alternate engagement and disengagement of clutches in differential assembly is usually caused by contaminated axle lubricant.
To correct this condition, drain and refill the rear axle with SAE 80W-90 GL5 (P/N 10950849).
The use of any additive in locking rear axles (G80) is not recommended. Rear axle additives are designed for use in limited slip differentials which are normally installed in cars. All light duty trucks equipped with RPO G80 make use of a locking differential and the use of additives will delay the engagement of the locking mechanism and may decrease axle life.
VEHICLES/COMPONENTS INVOLVED: --------------- Some light duty trucks equipped with locking rear axles, RPO G80.
SERVICE PARTS INFORMATION:
Part Number Description ----------- ------------------ 10950849 Lubricant, Rear Axle (1 litre)
Parts are currently available through CANSPO.
WARRANTY INFORMATION:
As specified in Light Duty Truck Maintenance Schedules, locking rear axle fluid drain and refill is required owner maintenance at the first engine oil change. Failure to drain and refill the rear axle as specified may contribute to a later axle chatter condition. Refer to the appropriate Light Duty Truck Maintenance Schedule or service manual, section OB, for further details on change intervals.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
© Copyright General Motors Corporation. All Rights Reserved
---------------
1988 V10 Suburban 5.7L TBI/TH350 39K on rebuild 4.10AR GM14FF/GM10SF 235/85R16 & 18.4-16.1

1988 V20 Suburban 6.2L-J/TH400 CA truck, 125K G80 14FF/ GM10 4.10AR GVWR 8,600

1977 Ford Granada ~450HP 302 2bbl/C4 27K original 2.47 215/70R14

Offline hatzie

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #3 on: December 28, 2016, 06:25:17 AM »
Regarding the suggestion to bypass the radiator cooler, i very rarely do that, up north here, only because from november until march our actualy temperatures drop below zero, usually 10-30F below zero for days or weeks at a time, 3 winters ago we didnt see a day above 0F for about 2 weeks, and i would not feel comfortable driving around a 6K lb vehicle with fluid that is probably alot thicker than designed for.  I have bypassed the rad cooler on motorhomes, but they rarely if ever saw a road after the first flurries hit the ground so it was no issue, and they usually cooled betterbc the fluid isnt getting passed through 180-220F coolant. I also understand that it is potentially possible to have a internal Rad leak and fry the trans if coolant went into it and thats the reasoning behind alot of people bypassing them, but the PO "claimed" this rad was replaced at a shop in cali just a couple years before it was parked and when i drained it and inspected it, there was extremely minimal buildup, so at the very lease it had proper fluid in it.

You really want to offload as much of the oil cooling as possible from the engine cooling system if you're towing with the 6.2L Detroit AMG engine.  It may be worth looking onto liberating a Serpentine belt system, dual thermostat coolant crossover, and high GPM water pump from a 1997 and later 6.5L.  The only gotcha is mounting the cable for cruise control, if you have it, and even that isn't terribly difficult...  It would be easier if the 1988-1993 throttle and cruise control bracket was still available.

That LPD plate cooler is reasonably thermallly self regulating.  My understanding is that when the vehicle is operated at low temps it mostly bypasses because the oil will not flow through the whole cooler at lower temps. Unlike engine oil it's not necessary to get the transmission oil temp above 240°F to drive out water and fuel from combustion blowby and running her at anything over 180-190°F for extended time periods will shorten the life of the transmission.  Automagic transmissions generate more heat than you might think even when the outside temps are very low.  For example the 4T65E-HD mated to the 5.3L LS4 V8 in my 2009 Impala SS with a long & narrow 20,000 GVW Tru-Cool LPD cooler self regulates at @ 150-170°F in the Northern NH winters and generally stays around 170°F in the summer. If you don't trust this or want a higher sustained ATF temp you can get transmission oil cooler thermostats but I'd install a trans temp gauge if you're running a thermostat. 

Interesting trivia...  If you look at the front bumpers on the 88-01 GMT400 Diesel and 3/4 & 1 ton GMT400 HD towing package trucks you'll see two cutouts.  These are to provide ducted air over the AUX trans & AUX oil coolers.

If you're serious about towing a lot you may want to get a full floating 10.5" rear axle to replace the 9.5" semi floating.  The Full floating hubs have two rows of tapered roller bearings that run on the outside of the axle tubes inside the hubs instead of a single straight roller bearing inside the tube.  The full floating diff bearings just carry the differential carrier side loads instead of part of the axle load giving you more axle load and possible trailer tongue load capacity than the semi floating design.

An axle oil temp gauge might be fun to look at but it's not at the top of the list of things you need for towing.  The axles will not get hot enough to worry about as long as the oil level is proper and the right upper temp viscosity.  You can get Aluminum covers with drain plugs that slightly expand the oil capacity.  The hype is that they will provide lots of additional cooling.  More oil will not hurt anything and a drain plug is nice but the rest of the hype is questionable at best.  IMHO they are designed to look good and lighten your wallet.  You'll get more utility from a good high temp rare earth magnet mounted below the oil level on the steel covers out of the way of the gears...  It's not a filter but it's cheap and it will at least pull iron from wear out of the axle oil.   
SVC & wiring mans --> Here http://tinyurl.com/7387BRD-SVCMAN or My Bucket @ http://tinyurl.com/SQ-SVCMAN
Parts & Illustr Books -->http://tinyurl.com/SqParts
GMSTG Textbooks-->http://tinyurl.com/STG-TEXTBK
Radio Manuals-->http://tinyurl.com/DELCORADSVC

Offline MuddiGGEr25

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #4 on: January 09, 2017, 12:56:12 PM »
Just thought id post an update since ive made some progress, well sorta.. the wifes02 volvo spit out the engine with a big bang and parts scatter across highway 9, had to walk partway home the other day with temps -10 to -15 wind chills in the -30's, so i just decided not to work on anything for a couple days after that and regain control of my fingers and toes.

I went and picked up another starter under warranty, this one came off of a 1995 K1500 with the 6.5L, its been too dang cold to finish tightening the support bracket. ive got the threads started a good 1-2 full turns but i was shaking too much mainly due to the high temp being 0F and my hands/arms are too big to fit above the axle with gloves or a coat so my hands and forearms were entirely exposed  :o :o , but ill tighten it up when i have access to a garage and/or heat lol.

I have been running off of 1 battery for the last several days i found out because the + had fallen off my secondary battery and was just dangling on the A/C lines.  The main battery is a napa legend 700CCA battery that i just prorated a warranty on (reg price $105, my price $30 with the warranty)

Now that i have installed the Airtex 8012S fuelpump to replace the junky 12D pump i was using, i have noticed the "random knock" at idle seems less pronounced, if there at all, I have plenty of "giddyup" but its also subzero and the incoming air is denser, it will be a better test once it warms back up above freezing.

Also with the new pump i no longer have to purge the fuel filter housing manually. I linked a video of a cold start at -10F or so the video begins right after the glow plugs had cycled on and off about 8 times, and it was plugged up for about 4 hours.

I also was able to start it at -6F after sitting at work for 8 hours with no sunlight or anywhere to plug it in, it struggled (probably due to only one battery) but it did kick off without me ever leaving the drivers seat.

The second video is my TBI mud truck build same day cold start literally 10 minutes before shelly, buy he was not plugged in and neither of them had been started in 5-6 weeks.


If your wondering i was holding the accelerator down about 50% because i rad on a couple forums that there used to be a sticker on the visor from GM stating when to partially hold the pedal when cold starting, but i dont have the sticker so I wasnt sure how much. and with the old pump it would not stay running unless i held the pedal to the floor until the air was purged from the filter housing.






I still intend on swapping in the 6.5l filter housing and probably a pump too if i can get a good deal off a wrecked pickup this spring, if not the airtec should be sufficient.


I think the 12D pump was too skimpy for my purposes, as i would run out of "ooomph" early and now i dont run out of "oomph" until around 25mph/2600-2700rpm, where it used to be around 15-20mph/ 1800-2100 RPM, If i am holding the accelerator down to get up to speed i.e ramp or heavy traffic it will not shift until 30mph/3200RPM which i think is pushing it a bit hard, i prefer to accelerate until 20-25, let off so it will shift to 2nd then accelerate more so that its in its powerband.

My only concern may be that my powerband is so low that i may slow to 50MPH or 35MPH going up the steeper grades in TN/GA. I mean its not a deal breaker, but i will find out once i hitch up to this trailer in a few weeks and see how it pulls before adjusting it for our trip.

Well the crew leader for our snow removal team just called so im gonna chill for the rest of the day till we go out tonight
« Last Edit: January 09, 2017, 01:03:43 PM by MuddiGGEr25 »
1988 V10 Suburban 5.7L TBI/TH350 39K on rebuild 4.10AR GM14FF/GM10SF 235/85R16 & 18.4-16.1

1988 V20 Suburban 6.2L-J/TH400 CA truck, 125K G80 14FF/ GM10 4.10AR GVWR 8,600

1977 Ford Granada ~450HP 302 2bbl/C4 27K original 2.47 215/70R14

Offline hatzie

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #5 on: January 10, 2017, 07:28:14 PM »
Sounds like you need glow plugs. AC Delco AC-60G PTC (Positive Temperature Coefficient) glow plugs are a must.  They're dual coil fast start units that self regulate.  On top of that they don't swell up when they fail... unlike the obsolete AC-9G & AC-11G glows.

Replace all eight.  That way you know what you have.  Right now you could have a mix of old obsolete 9G & 11G plugs along with current design 60G plugs...  mixing in the old slow glows is not a recipie for easy starts and the obsolete designs swell up when they fail.



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Offline MuddiGGEr25

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #6 on: January 10, 2017, 09:09:02 PM »
Sounds like you need glow plugs. AC Delco AC-60G PTC (Positive Temperature Coefficient) glow plugs are a must.  They're dual coil fast start units that self regulate.  On top of that they don't swell up when they fail... unlike the obsolete AC-9G & AC-11G glows.

Replace all eight.  That way you know what you have.  Right now you could have a mix of old obsolete 9G & 11G plugs along with current design 60G plugs...  mixing in the old slow glows is not a recipie for easy starts and the obsolete designs swell up when they fail.



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I dont understand how it sounds like i need glow plugs, when i say its negative 20F outside i mean thats the real temperature, NOT the wind chills, our wind chills have been dipping as low as 50 below zero. the 6.2 started outside after a 8 hour shift at work with only 700 cold cranking amp battery connected, and i usually let the glow plugs cycle several times just to let the heat radiate into the surrounding metal, it "will" start off of a single cycle of the glow plugs but it doesnt pop right off at -20F with 1 battery and no block heater.

I know that my 6.2l is not the same as a 12V or 24V 5.9L, or a 7.3L but i can say confidently (because i run a service truck and i used to work for a tow company) that i have witnessed newer diesels with fully functional glow plugs even on the dealership lots that WILL NOT start at -20F off a single cycle of GP's if they are not plugged in. 

Even the diesel plow trucks at work, and we have a variety of 7.3L, 6.5L, 6.6L, 5.9L, even in the enclosed shop (not heated but usually above 0 in there) some of them wont pop off without cycling the key a couple times. and they are religious about the maintenance.

Im sure the upgraded glow plugs might help, but i dont believe mine are malfunctioning yet, because the last few days i have had it plugged in at -12 to -20F before i leave for work in the morning, and if i crank it immediately after the GP light goes off it does start immediately and will cycle the glow plugs for the first few minutes of running. 


I am fairly sure the 15W40 at -20F makes it hard to turn the engine at those temps with only 1 battery. i got off work today at 5am and it was about 3F above zero and i just waited for the GP to shut off and it fired right up, but my cold idle thing doesnt do anything plugged up or unplugged so thats probably not helping either.
1988 V10 Suburban 5.7L TBI/TH350 39K on rebuild 4.10AR GM14FF/GM10SF 235/85R16 & 18.4-16.1

1988 V20 Suburban 6.2L-J/TH400 CA truck, 125K G80 14FF/ GM10 4.10AR GVWR 8,600

1977 Ford Granada ~450HP 302 2bbl/C4 27K original 2.47 215/70R14

Offline hatzie

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #7 on: January 10, 2017, 10:22:55 PM »
The 5.9 has a grid heater not glow plugs.

Of course they fire right up after plugging them in.  My 6.5 is at close to full operating temp in 3/4 of an hour plugged in. 
My 6.5L & both 6.2L will start right up at -30°F on three cycles without being plugged in.  They have none of the firing on one cylinder twice or three times and then not firing at all your truck was exhibiting.  That's usually a symptom of several, six or seven, bad glow plugs or low compression.  Your rigs were running OK within a few seconds when they finally caught... Air in the fuel system usually doesn't work its' way out that fast and low compression wouldn't lend itself to smooth running.

The GM controller cycles regardless of the glow plug condition.  It's a thermally controlled timer and high amperage contactor.  There's no glowplug condition sense just a thermal inhibit and thermally controlled after-start cycle.  The contactor closes and cycles regardless of whether there are electrons flowing through the glows.

Cranking speed is adversely affected by 15W40 at -20°F.  I run Synthetic 5W40 Diesel oil, either Mobil1 Turbo Diesel Truck or Shell Rotella T6, year round.  They are much happier to kick off at -10°F to -40°F and the oil pressure shows instantly on the gauge.

It's easy enough to test the glow plugs and high amperage delivery wiring.
-Dig out your DMM plug in the probes for resistance testing and set it up for the lowest ohms scale.
-Unplug the glow plugs.
-Test from the glowplug body to the connector tang.  It should read 0.8Ω to 1.0Ω for AC-60G glow plugs. 
-Each glow plug wire is protected by a fusible link....
--With the key OFF test from the glow plug female connector to the controller output stud.  If a wire reads high or infinite ohms the fusible link is blown.
« Last Edit: January 10, 2017, 10:25:22 PM by hatzie »
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Offline MuddiGGEr25

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #8 on: January 10, 2017, 10:31:31 PM »
I will try those tests later this week when it's sunny and above 0 again lol.  I did read somewhere that I should have about a 100 amp draw with all 8 functioning. and my voltage drop showm on my multimeter would lean towards 80+amps being drawn because I drop from about 12.2V (depending on state of charge obviously) to roughly 10V while the glows are engaged.

I'm not against changing to the self limiting newer style plugs. I just can't afford to do it atm with only getting 10-15 hours at work right now.
1988 V10 Suburban 5.7L TBI/TH350 39K on rebuild 4.10AR GM14FF/GM10SF 235/85R16 & 18.4-16.1

1988 V20 Suburban 6.2L-J/TH400 CA truck, 125K G80 14FF/ GM10 4.10AR GVWR 8,600

1977 Ford Granada ~450HP 302 2bbl/C4 27K original 2.47 215/70R14

Offline MuddiGGEr25

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #9 on: January 10, 2017, 11:38:04 PM »
What do you mean, "close to full operating temp" after being plugged in after 45 minutes? what are you using for a block heater? ive got the freeze plug style and i believe its 600W, its not enough to make my 100ft extension cord get warm so i know its under 10A, because my 1000W space heater will make the cord get warm after a couple hours.


My temp guage is still bottomed out after sitting all night plugged in and not even luke warm air out of the vents.I have blocked 1/2 of the radiator by using cardboard between the rad and the AC condensor.

If i let it idle i will begin to get warmish air from the vents after about 30 minutes, and the temp guage will be around 1/4 up and will not go any farther unless it is warmer than 35-40F outside. even when driving aggresively i cant even get to proper operating temp (about the middle of the guage) and once i stop moving it cools back down

It should be noted that this was a california truck, the PO told me it has the biggest HD/Towing cooling package to be able to spend hours in the nevada desert visiting families, and it has a flex fan instead of the standard temp clutch design.  They also had the rear AC installed as it would be over 100F in the back row during the summer. so that it probably not helping matters.

AC system does not engage when i turn on defrost so its probably low on R134a
1988 V10 Suburban 5.7L TBI/TH350 39K on rebuild 4.10AR GM14FF/GM10SF 235/85R16 & 18.4-16.1

1988 V20 Suburban 6.2L-J/TH400 CA truck, 125K G80 14FF/ GM10 4.10AR GVWR 8,600

1977 Ford Granada ~450HP 302 2bbl/C4 27K original 2.47 215/70R14

Offline hatzie

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #10 on: January 11, 2017, 04:31:24 PM »
The gauge picks up off the bottom stud and there's heat from the defroster vents without running the engine for more than a few seconds.   It's a 1,000 W dealer installed frost plug heater in the 2000 C2500 GMC...  I assume OEM GM.  1,000W aftermarket freeze plug heaters in the others.  You can replace the cords if they are crunchy and I usually grease the heck out of the terminals with dielectric grease.  The terminals usually clean right up with toothbrush size brass brushes.  If they don't clean up replace the heater.
If you're regularly seeing below -20°F you should put one on each side of the block.  I only occasionally see -30°F and usually not less than -15°F.

NEMA 5-15 is 15Amps at 120V or 1800W max.  NEMA 5-20 is 20A at 120V or 2,400W max.  If the heater is 600A you should only be pulling 5A.  Well under the 15A max NEMA 5-15 plug threshold.  If the cord is getting hot my guess is you're using 16-3 extension cords with a long run or that block heater is bigger than you think it is.  The smaller gauge cords or long runs burn your wattage instead of your block heater.  You can buy 25' 12-3 extension cords for right around $40.  You shouldn't plug it in further away than 25' or so and shorter is better.

My 12-3 SOOW cord is run is no more than 12'.
« Last Edit: January 11, 2017, 04:52:02 PM by hatzie »
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Offline MuddiGGEr25

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #11 on: January 11, 2017, 05:55:56 PM »
The gauge picks up off the bottom stud and there's heat from the defroster vents without running the engine for more than a few seconds.   It's a 1,000 W dealer installed frost plug heater in the 2000 C2500 GMC...  I assume OEM GM.  1,000W aftermarket freeze plug heaters in the others.  You can replace the cords if they are crunchy and I usually grease the heck out of the terminals with dielectric grease.  The terminals usually clean right up with toothbrush size brass brushes.  If they don't clean up replace the heater.
If you're regularly seeing below -20°F you should put one on each side of the block.  I only occasionally see -30°F and usually not less than -15°F.

NEMA 5-15 is 15Amps at 120V or 1800W max.  NEMA 5-20 is 20A at 120V or 2,400W max.  If the heater is 600A you should only be pulling 5A.  Well under the 15A max NEMA 5-15 plug threshold.  If the cord is getting hot my guess is you're using 16-3 extension cords with a long run or that block heater is bigger than you think it is.  The smaller gauge cords or long runs burn your wattage instead of your block heater.  You can buy 25' 12-3 extension cords for right around $40.  You shouldn't plug it in further away than 25' or so and shorter is better.

My 12-3 SOOW cord is run is no more than 12'.

I just checked the cord its a 16-3 orange outdoor extension cord, its running out through a window on the side of the building, and it literally BARELY reaches the truck, i have a 20A cord i made for when I am plugging the camper in, it has a 20A 110V male plug on one end and i put a junction box on the other end with both the RV style 30A plug and a regular 15/20A household outlet, i used 10-3AWG for that one and i have another one i made that has 12-3 wiring but only have a 15A male, and 1 junction box with a 15A receptical, but these are only 25FT long, because i made them just to extend the camper cord which was already 30FT

I should have been more specific, if i run a 1000W milkhouse heater to warm up/de-ice the windows in the truck, the cord where it plugs into the wall in the apartment gets really warm at 1000W for extended periods, but it does fine with my 500W floodlight.

The cord outside does not warm up, it only gets stiff under -10F

I was considering getting a 1000W inline coolant heater on the lower rad hose and just plug in both, but i have heard conflicting stories whether they restrict flow. i dont want to restrict flow if i am towing in the south, but then again that might be a moot point as im getting a 1991 F350 in about a month, tow rating of 12,500 says the book, and its had almost everything gone through in the last 1500 miles, they just need to sell it to fund thier 7.3l build, i know i know this is a chevy forum so please no bashing lol, im a chevy guy but its a crew cab 1ton i couldnt pass it up for $600


Back to my guage, its not moved even after being plugged in 24 hours, or if i have it up to temp, and get home and plug it up, by the time i go to work at midnight the temp guage doesnt register anymore, until its been running atleast 5-10 minutes.

I am trying to get the landlord to rent me one of the garage stalls so i can utilize the power there and plug/park it inside where i can keep it sorta warm
1988 V10 Suburban 5.7L TBI/TH350 39K on rebuild 4.10AR GM14FF/GM10SF 235/85R16 & 18.4-16.1

1988 V20 Suburban 6.2L-J/TH400 CA truck, 125K G80 14FF/ GM10 4.10AR GVWR 8,600

1977 Ford Granada ~450HP 302 2bbl/C4 27K original 2.47 215/70R14

Offline 1967KaiserM715

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #12 on: January 11, 2017, 09:13:10 PM »
on cold starts, GM does mention holding gas down till start, one reason is so the High Idle will kick on(it can not push the throttle open, but it can open it.)

IF your cold advance and High Idle are not working it may be a bad switch in the rear of the passenger head. this will make cold starts much easier.

I also recommend going through glow plugs and wiring, getting rid of any questionable fuel lines(read possible leaks) and running 5w40.
Current Vehicles:1985 GMC K10(Daily) 1991 GMC K2500(Daily) 1975 Beetle(not running) 1985 Mercedes 300D(not running) 1952 M35    1967 M715(not running)
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Offline hatzie

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Re: Preventative measures for a 6.2L IDI detroit
« Reply #13 on: January 11, 2017, 10:19:11 PM »
Your block heater may not be all that it was in 1988.  You can buy brand new 1,000W freeze plug heaters for around $65.
Kats and ZeroStart make 1500W tank and pump heaters that will install in one of the heater lines.  You're SOL if there's nowhere to plug it in.  We ran one on a 1967 International 656 when I was a kid.  You couldn't touch the heater hoses or the block after about 30 minutes without getting burned but it was stored in a pole shed where the wind wasn't stripping away the heat. 

Webasto makes a sweet compact diesel burning coolant heater that's way way way out of our price range new.  Something like $2,000. OWCH!!! LOL.  Espar makes one too but it's even more money.   If you can liberate a working used one from a piece of construction machinery or tractor trailer it's probably almost reasonably priced but then you need to service it before you install it.   If you feel like fabbing a home for a small furnace the Proheat units off used up city transit coaches work extremely well... but they are big and bulky and require 24v electrical...  and again you need to service them.

I did the hunt for a plug everywhere I went in the winter when I was 20 with a 1979 VW 1.5L Rabbit Diesel that had one good glow plug.  She started just like your truck at 30°F  at 0 don't even think about it.  When I finally saved my pennies and bought 4 glow plugs it kicked right off at -10.  It really is much cheaper and less stress to replace a handful of glow plugs and fill with winter friendly synthetic diesel lube oil.  AC-60G glow plugs are $9.09 US each with Free 2 day Amazon Prime shipping so eight at $72.72 are right around the cost of a Kats tank heater.
« Last Edit: January 11, 2017, 10:33:50 PM by hatzie »
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