engine swap 6.5 back to a 6.2

[CGarbee]

Yep, I know this sounds backwards to a lot of folks, but...

Got a buddy who scored on a HMMWV with a blown 6.5. He then scored on a few 6.2 engines (rebuilt, HMMWV, with all the accessories on them in the can). So, we need to stick an engine into his ride.

He remembers having this done overnight when his Guard unit was in Iraq, but he wasn't the one doing the wrenching.... I'd ask the guys in the shop behind the office, but they are all currently deployed...

Is the wiring hareness the same? I'm thinking that he/we will have to tweak the exhaust, but what else are we looking at having to tweak/change to get this to work?

Thanks in advance...

 

[Chief_919]

What model HMMWV is it with the 6.5? Turbo or NA? What transmission?

1. If it is a NA truck with the THM400, you will have a bolt in.
2. If it is a turbo truck, you will have to swap out the heads and intake to keep the turbo, as the NA engines and side mount turbo engines used one set of heads, while the center mount turbo engines used another. If the 6.5 is blown and the heads are bad a set of heads from a civilian 6.5 in a van (and only the vans) will fit. The intake studs for the manifold in the center mount turbo are at a different angle to make room for the turbo.
3. If it has the 4L80E transmission you will have to swap out the TPS on the injection pump and recalibrate it. I have the instructions on that if you need them.
4. If your truck has the serpentine belt you will have to swap out all the accessories on the front.
   

Hope this helps a little. I have done about ev er manner of HMMWV engine swap out there at one time or another, from shoehorning a 6.5 turbo in a M998 to putting a CUCV 6.2 in a M1114 with the turbo on it.

 

[cavtrooper]

It has the 4L80E 1995 or 1996 model. can you send me the instructs on the tps recal? I am also having problems with the wiring harness. do you have any suggestions or hints Do you still come to bragg anymore? What would you charge per hour of your time to help trouble shoot the 6.2 which is installed now. I am only getting fuel out of i line from the injector.

 

[jwaller]

give me a call next week, I'll be happy to help. 803.546.1897