'94 GMC 6.5TD Donor for M715?

[tmuenster]

I was looking around for engine options for my M715 and found an ad for this truck:

1994 GMC 6.5 TURBO DIESEL 5SPD NV4500
The truck has 217,000 miles, 5 speed manual transmission, 4X4. Heads and head gaskets were done roughly 2000 miles ago and the clutch 2500 miles ago. Glow plugs, starter, cv axles, radiator have been replaced recently. Everything works and has plenty of power for pulling and very reliable. It smokes for a little bit on a cold start but clears up and runs awesome after that.

The asking price is $3,000 but I think it would go for around $2K.

Please let me know if you think this would make a good donor for an M715 build.

Thanks,
Tom

[jeeper]

What do you plan to do with the truck?

First off I will start by saying the 6.5 isn't a terrible engine. I have one myself but it isn't installed in an M715. I did have an M715 with a 6.2 diesel installed with an otherwise stock drive train. It was loud and slow but I liked it a lot.

You may already know this but I will type it out anyway just in case.

The 6.5 diesel doesn't do well with high rpm's. Also it is not a power house engine. Compared to the more modern offerings it is lethargic. In '94 I believe the injection pump was electronically controlled also and the PMD was plagued with overheating problems because of the mounting location.

The PMD problem can be overcome a couple different ways. You can get a relocation kit and heat sync or you can swap the electronic pump for a mechanical pump that doesn't need the PMD.

If you plan to swap only the engine I wouldn't bother buying an entire truck to get it.

If you plan on swapping in the engine and transmission married to the transfer case you will have a problem to overcome as well. The 94 Chevy front differential is on the drivers side so the transfer case won't work with the stock M715 front axle.


It would be easier to give better answers if we had more information about what your plans were for the truck and how much of it you are able to do yourself.

[tmuenster]

What do you plan to do with the truck?

I am considering re-powering my M715. The SBC seems to be the easiest swap but I would prefer to have a diesel engine in the truck. My thought was the '94 GMC drive train could be transplanted in the M715. I have learned the '94 GMC has a driver's side transfer case and the turbo would also cause some problems with the firewall on the passenger side.

[Mikel]

Doesn't a 94 have IFS?

[Barrman]

Yes, driver side drop IFS. I think it also has the bell mounted slave for the NV4500 which will interfere with the passenger side drop M715 front drive shaft.

Then there is the center mount turbo which won't clear the M715 fire wall without some cutting.