thinking about doing a diesel conversion on my suburban

[87suburban]

i got a 1987 Chevy suburban 3/4 ton 4x4 with a TBI350 and a TH400 trans, an I'm thinking about doing a diesel conversion to get rid of the 350. Now I've been thinking about putting either a 6.2L or a 6.5L turbo diesel in it, considering it would most likely be fairly easy since it'd be almost like a direct bolt it. I know that stuffing a B-series Cummins in it would probably be the way to go, but everyone an their grandma put a B-series cummins in something and i want something different. Then i got the idea of putting a Duramax diesel in it, but don't know what kind of problems that i'd run into while trying to put it in my truck. Anyway, if anyone has done a diesel conversion with a 6.2/6.5 diesel or a 6.6 Dramas, can y'all tell me what issues are involved and how to address them? Right now, I'm just trying to get an idea of what I'd be up against when I'm able to it.

                                                                                                   Thanks,
                                                                                                   Ron

[Camfirchev]

 I have never gone that direction but I have a couple things to throw at ya..  You will need to change over your Vacuum Brake Booster over to Hydroboost,  Lower stall Converter for your Trans,  Larger Radiator and Shroud.  IMO I would start looking for a good running "Complete... Oil Pan to the Air Cleaner" 6.5TD and use an injection pump from a 6.2 to Eliminate the ECM and all the Electrical that came with them from the factory.  You might want to look into the gearing you will be running also??   If you paln on going this direction, I am doing a Gas conversion and I might be able to help you out with some of the parts you will be needing... at no cost to you!!  Just give them a nice home.

[87suburban]

oh i thought the 6.2/6.5's ran vacuum pumps on them, or was that just the 6.2? oh so the converters that are used for gas an diesel engines are different? i didnt think there would be any difference between them. in that case would it better to get a converter that would have come with the 6.5LTD? and if thats the case would it work with a TH400 trans? but if i put a pump from a 6.2 on a 6.5 TD, wouldnt that cause problems considering the 6.5 pump is a DB4? then for the gearing, do you have any recommendations on what i should run in it? i didnt realize that the gearing would most likely need to be changed, cause i was just going to use what gearing my truck already had in it. oh, ok hey thanks

[Edahall]

If you're going to go through all the trouble to convert it, go with with Cummins.  The 6.2 would have less power than the 350 that's currently in your Suburban.  The 6.2 only came with 135 hp and about 250 lbs of torque.  However, where the 6.2 shines is fuel economy.  If it's set up correctly, it can pull in close to 30 mpg.  But behind a TH400 and 4.10 gears, you'll be severly limited on speed and fuel economy will suffer.  For best fuel economy, you would need to use a transmission with an overdrive and lock up torque converter or 5 speed manual and a 3.43 rear end.

[Captkaos]

I am in the process of doing this to my Camo Blazer right now.  I just got the 6.2L in it last night.  I am trying to figure out the wiring now (I HATE Wiring) and I am desperately trying to find AC brackets for it.

[87suburban]

To: Edahall
well i could run the Cummins, but everyone an their grandma put a Cummins in something an i want something different.  i dont know what gears my suburban has, i found one place that has like a spec sheet if ya want to call it that. Looking on there it showed that 3:42 apparently the standard ratio, but i dont know if thats what is in my suburban. havent pulled the covers off to see what gears are in it yet, but would bolting a 700R4 behind one be better than my TH400?

To:Captkaos
oh, now did your blazer have TBI or carb? i know what you mean, cause my truck has TBI and that cause me a head ache trying to wire up a 6.2?6.5 TD in it. however i think im leaning more to the 6.5 TD to put in it.

[beastie_3]

The reason everyone and their grandma put a Cummins in something is because the Duramax and Powerstroke usually arent worth the swap effort.

[87suburban]

i havent really heard anything bad about the duramax's, but with the power strokes starting with the 6.0L they are nothing but junk even though they have power. but the thing with the cummins, is the 5.9 has some fatal flaws though an i just want to do something different to mine.

[beastie_3]

as long as you stay away from the "58" block on the 24v and make sure you replace the pump before it goes out, then you should be fine. the 12v has just as much power potential, if not more, and you dont need to worry about electronics. There are more parts available for the cummins swap vs the duramax or power stroke. a later model 7.3 would be fine. earlier models had problems.

[87suburban]

i thought it was the"53" blocks that were bad, an with the 12V they had the "killer dowel pin". u mean changing the injector pump on the 24v? well if i was going with during a duramax swap, id like to find a donor truck to use.

[beastie_3]

53. I couldnt remember ha. ya the dowel pin is a easy fix, well worth the time to do it before it destroys the engine. Yup, injector pump problems.

[87suburban]

well with the injector pump issues, aren't the lift pumps that are used with the VP44 the reason why that pump has its problems?

[beastie_3]

I dont know the details, I just know of the issue. I was looking into getting a 24v a while back. A search of a Dodge or Cummins forum would get you the answers.

[Edahall]

To: Edahall
well i could run the Cummins, but everyone an their grandma put a Cummins in something an i want something different.  i dont know what gears my suburban has, i found one place that has like a spec sheet if ya want to call it that. Looking on there it showed that 3:42 apparently the standard ratio, but i dont know if thats what is in my suburban. havent pulled the covers off to see what gears are in it yet, but would bolting a 700R4 behind one be better than my TH400?

Why is a 6.2/6.5 different in a Suburban?  Quite a few were sold with that option.  My 1982 Suburban came stock with the 6.2 and I rebuilt the engine and made some modifications to increase the power.  It gets excellent fuel economy and power is decent but power is not even close to the Cummins in my 1990 Suburban.  The 6.2 pulls my 26 ft Airstream alright but a little slow on the hills but with the Cummins, you hardly know it's behind.

[87suburban]

Edahall:
i dont think there is any difference between the 6.2/6.5 in the suburbans, i just need to know what all problems i'll be running into putting a 6.2 or 6.5 in my suburban. The thing with my suburban is it has a TBI 350 with a TH400 trans and i dont know what the axle ratios are. Now so far, it looks as though im going to have to change my axle ratios maybe, possible tranny, and the radiator/fan shroud. now aside from that, i dont know what else im going to have to do. Another problem is dealing the electrical, along with if i go with the 6.5 TD i think the injector pumps had electronic module on it (i think you could call it that). Then i've was told to solve that problem, was to swap a 6.2 pump on it but i dont think it'd work considering the 6.2's were never turbocharged and the 6.5's were.

beastie_3 :
im pretty sure that what kills the VP44 is the lift pump that is used, now i think even running the engine stock the transfer pumps still killed the VP44