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6.5 Turbo Diesel Swap to 79 GMC 35 DRW

TJS

PlowSite.com Addict
Location
Fairfield,CT.
Looking to swap in a 94-96 6.5 TD into a GMC 35 (2 wheel drive dually). It was my Dad's welding truck. He passed in January. The truck has no rot at all. Just patina on the hood. It has a utility body loaded with tools, Lincoln weldanpower 250 (onan). A large air compressor driven by a willys engine that is crazy. Anyway, it has a tired 350 in it and a Muncie rock crusher trans. and it has hydroboost as well (so vacuum is not a prob). I want to find a running donor with a 6.5 TD and swap it. I know about the dual mass flywheel where I would have do the flywheel/clutch conversion. I have been online looking around and all the vids are terrible and some of chevy truck forms have the typical missing information.
I don't want to hear how bad the 6.5 turbo diesel is. I leave that up to DeBoss Garage on YT. And no I don't want to go Cummins 12 route either. Just looking for someone who had done it and had some technical info to share. Like "hey it can be done but you have to lower the crossmember so the oil pan fits". I know I can make the motor mounts and crossmember if need be as I have some tools.
Thanks for your input.
 

Philbilly2

PlowSite Fanatic
Location
Sandwich IL
I am no help on the swap as I have only been around removing 6.5's from trucks to put other motors in.

I have only one question... why are you so set on a 6.5?
 
OP
T

TJS

PlowSite.com Addict
Location
Fairfield,CT.
This is actually an "In Memory of" project and I want to keep it GM and don't want to mess with bellhousing adapters for the GM trans that is in it.
 

Kinport

Senior Member
Location
Powell Wyoming
I have not done this swap so take my advice for what it’s worth-

Why are you wanting 94-96 model year? I ask because engines built after 1994 came with a ds4 fuel pump as opposed to the ds2 that was used prior to 1994. ds2 is mechanical injection, meaning you won’t need a computer to run it. No pcm to switch, no complex wiring, no PMD, generally more reliability are the benefits of using the ds2 pump. Of course, you can convert 94 and later to ds2 if you wish.

Motor mounts should line up.

if the 79 Has a/c I think the evap box will get in the way of the turbo.

I would upgrade the radiator while the motor was out of the truck. The 6.5 always struggled with getting hot and there’s a lot of modifications to prevent that but a quality radiator will be key.

I’ll post more if I can think of anything. I wish you luck on your cool project and hope you’ll keep us updated with pics if you decide to pull the trigger
 
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OP
T

TJS

PlowSite.com Addict
Location
Fairfield,CT.
Yes. The more and more research I do a 93 truck would be the best bet. A 93 truck. However finding a donor for that year is key. Thanks for the tips.
 

sweetk30

PlowSite.com Addict
mech injection pump for the win . aftermarket turbo for better results .

stock 6.2 diesel rad swapped in . guys do the d-max fan on the llater 6.5 turbo water pumps for a bolt in swap and it helps a tons .

and as said why the 6.5 diesel ? 140-160 ish hp and the problems they have . do some hard reading before you go the 6.2 or 6.5 route .

if you can find a p-series bread truck they had 4bt cummins and gm adapter plate to a stick shift or th400 or 4l80-e trans and bolt in to gm trucks easy with the mounts on them also . but we know cummins stuff is $$$$$$
 
OP
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TJS

PlowSite.com Addict
Location
Fairfield,CT.
Ok. I bought a 1994 k3500 GMC 6.5td, rebuilt 4l80 (1k on rebuild). Dump body (well what is left of it..so rusted) with a 9ft fisher MM1 insta act pump that works lol. The mold board is swiss cheese..lol. Engine was replaced 80k ago. PO had receipts. Heath remote mount PMD set up. Cab is rusted to nothing left. Frame surprisingly is not rusted (yes, surface rust, needs sandblasting). Truck did not run. I towed it home. PO said it ran out of fuel. No-no, you had a bad lift pump and cranked the snot out of it. Smoked the starter so bad when I took the bush cap of the starter off the solder on the brush tabs got so hot they de-soldered. I have a starter to go back in. Going to get it running this weekend to make sure I have a running truck. Using my own make shift fuel feed pump set up and separate fuel tank too. Got truck for 750.00. If it is a total loss I can part it out and make my money back. The lift pump and cyl work and the cyl is huge.

Ok here is my plan: flame away you animals. I am going to swap the 79 cab onto the 94 frame. Wheel base is about 1.5" difference. The 79 has a utility body and I will find some wiggle room there. I already have cab mount design programmed for my CNC plasma cutter. Oragami style.
 

Philbilly2

PlowSite Fanatic
Location
Sandwich IL
If it was cranked to death... you might need to make sure the PMD that was relocated is still good. They will crank forever with fuel present and still never start if that little stupid box is bad.

Just FYI
 
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