3 speed to a 4 or 5 speed swap not sure and confussed

[heyharris1]

oki, i bought a 1986 checy c30 i ton dullie truck, it has a 4 speed tranny kinda, the first gear is  actually a granny gear then 1-2-3 gear and reverse. the truck has 4:10 gears in the rear end. i would like to change it over to a normal 4 speed without granny gear or 5 speed if possible since i will be doing alot of highway driving and not really pulling a extremely heavy load. the truck has a 454 engine in it. also if i leave it alone is 3rd gear a 1:1 ratio. i dont know what kinda tranny is in it right now. thank you all for the help.

[Captkaos]

3rd is 1:1, the transmission is a SM465.  There isn't a transmission that I would put in a 1T dually that doesn't have a granny first.  I would consider a NV4500 though.

[heyharris1]

oki ty very much. if i go with a nv4500 how hard is it to swap, something a normal person can do or will it take someone with extreme knowledge in tranny swaps.

[Captkaos]

How mechanically inclined are you?  I won't say it is a simple swap.

[heyharris1]

i was a mechanic in the army for about 4 years and can do basic stuff like brakes, even changed a couple engines but with the same kind, so did not have to worry about modify anything. if i can just unbolt and bolt then im good but if i have to manufacture coss members and such i may just leave it to a professional

[Captkaos]

Here is some info:  Advance Adapters should have a kit for these.

http://www.fourwheeler.com/projectbuild/1971_chevy_suburban_engine_transmission_replacement/index.html

http://www.high-impact.net/transmission_and_gear/nv4500_gm82-93diesel.htm

[Blazin]

 Gear Vendors under / overdrive unit might be something worth looking into?

[heyharris1]

thanks for the info guys, i really appreciate it

[hilton850]

x2 on the gear vendors overdrive....only downside is price

[Irish_Alley]

a couple questions what is this nv4500, as much input on it as you can and whats the gear vendor overdrive, i know what over and under drive kit for engines would think its about the same for the tranny but what does it do. and with my 465 would changing to a trany with more gears hurt it in the mud, highway and mpg. one more question having a clutch problem with it slipping when i want to have fun more so in 4x4 its OK till i floor it and same with 4x2 most time its OK till i take off to fast well a slow take off then gunning it, on more thing iv noticed white smoke not all the time but once in a blue moon roll from behind my truck during a deceleration with the clutch still engaged and not using breaks

[hilton850]

There are a few companies that make overdrive units, gear vendors is one of them.  Basically they build a two speed gearbox that bolts on the back of your transfer case.  The details are on their website:  http://www.gearvendors.com/index.html  There is another company that makes the ranger overdrive at: http://high-impact.net/transmission_and_gear/rangeroverdrive.htm  These are a little different since they go in front of your transmission so you CAN use them in 4x4 but sounds like a lot more work to get them to fit and it says on the website they're only rated for 420 ft-lb...your 454 may make more than that...you can read all about it on their website.
As far as your clutch goes, it sounds like you need a new one.  I've had good luck with a centerforce dual friction clutch from Jegs if you wind up getting a new one. 

[Captkaos]

The NV4500 is basically a SM465 with overdrive.  It came in 1992 and up 3/4T and up trucks and also in Dodge HD trucks.

If you clutch is slipping on acceleration you need a new one.  I don't like centerforce for street use as the flyweights actuate on rpm.  For a street/strip car they are great, but for mostly street, I use Zoom clutch assemblies.  I had one behind the 454/4speed when it was running and it was still good when I pulled it apart.  And I abused it and street raced it often.

[Irish_Alley]

the clutch in it ain't old like maybe a couple months old but its just a dd clutch from autozone thats were the problem is its just not built to hold up under all that strain of the 38s

[hilton850]

What size clutch is it?  (I don't know if all the GM trucks came with the same size clutch or not) and you're right...if it's a stock replacement it may not hold up to a more powerful engine or bigger tires as well as a good aftermarket clutch.  I have a few friends who can kill cheap clutches in a couple weeks...say nothing about a couple months.  I tend to agree with capt...slipping on acceleration is bad and probably means you need a new one. 

I have a 12" centerforce dual friction clutch...I use the truck for plowing snow, towing and truck pulling...I don't baby it by any means and it has held up great, even behind the 383 screaming down the track for all it's worth at the pulls (if you've ever done any truck pulling you know that will put some strain on the clutch).  I personally don't think it feels much different than the stock clutch did.  As far as streetability goes I never noticed any difference from stock except this one has lasted longer...mine still lets out when I take my foot off the clutch and engages as smooth as the stock one did.  I believe that centerforce does make some more aggressive racing clutches....and I have also heard that those are a little different like capt. says, and use weights to engage.  Mine is different...only uses weights to add clamping force after the clutch is already engaged.  Anyway these are just my personal experiences and opinions and we all know how those are. 

I've also heard good things about the zoom clutches but have never used one.  My brother has one in an '83 3/4 ton and hasn't had any problems that I know of and he uses that truck about the same as I use mine...except sometimes he thinks it's a skidder and drags firewood out with it...I really think you'd be happy with either one.

[Irish_Alley]

i think for this trany they did have the same size but they had an option for w/ or w/o a diaphragm if I'm thinking right the one we put in was w/o it had the multiple center teeth not sure what there called and the diaphragm hand like 3 or 5 I'm thinking more like 3. i mean i 4x2 it hardly acts up, its just mainly in 4x4. but eather way i think the aftermarket clutch will fix all the problems, just have to convince her maybe burn this one up