GMC 6.5 Turbo/4L80E?

[ATNC325]

I ran across a wrecked 2002 GMC van w/ 4L80E that I was inquiring about to use as a donor vehicle for a potential tranny sway in my m998. Turns out it also has the 6.5turbo diesel in it as well and I currently have the 6.5 n/a. Is there any compatibility between the civilian and military engines and/or turbo components? Or does the whole 12v vs. 24v make it a no go....just peeked my curiosity at bit, but I'm sure the lack of rumbles of hearing anybody else doing this probably is because they are just different animals. Let me know if there's anything engine/turbo wise worth grabbing while I'm taking out the transmission. Thanks in advance!

 

[TOBASH]

The turbo engine will fit but you need to swap out anything electrical for 24 Volt

 

[Bulldogger]

Check if it is a centerline, rear mounted turbo, or more typical side-mounted forward. Conventional side-mounted turbos will not fit in the HMMWV narrow engine bay. Sorry to rain on your parade, but I am not aware of a common rear mounted turbo civilian diesel truck.
Bulldogger

 

[NDT]

GM Vans do indeed have the rear mount turbocharger. The 4L80E will need to be completely disassembled to have the tail shaft replaced with the shorter 4 wheel drive version. It's even possible the engine is a Navistar cast block, GM quit making 6.5s in 2000.

 

[springer1981]

I'm not so sure it wouldn't be easier to convert it to 12v. Depends on if you plan on using all the stock accessories like the glow plugs and controller, alternator and any other 24v system. The 4L80 needs to use a controller and (just a guess) the new engine probably uses an ECM tied to the TCM. If you keep everything off the van you won't need an ECM, TCM, wiring, new glow plugs or any of the other related stuff. To go 12v, you mostly just need to change light bulbs. Just a thought to consider.

 

[NDT]

The van has one computer that controls the 4L80E and the DS-4 electronic injection pump. Removing that computer and attempting to make it work in a HMMWV would be an absolute nightmare. The DS-4 sucked when it was new.

 

[Action]

The HMMWV TCM is a 12v GM unit. Just stuck in a waterproof box.

 

[Bulldogger]

I used EZ-TCU for the transmission control and had/have few problems. Others used US Shift and it went well.
BDGR

 

[Crazyguyla]

You could put the njection pump off the 6.5n/a on the 6.5 turbo. I don't remember if the turbo wastegate is tcm controlled.