Chevy Diesel Engine Swap

bourban driver · Post by **bourban driver** » Wed Apr 25, 2007 10:10 am

Guys -- I'm planning a road trip across country, down through Baja, over into Mexico, and ultimately into South America. It's been in the works since 2000, and I've re-commited to it after reading "In Search of Captain Zero." Yeah, it'll take a couple of years, and yeah, we're crazy. But to do it, I'll need a diesel in my truck. Previous trips to Costa Rica and Mexico reiterates that regular gas is really hard to come by while diesel is everywhere. I've found a suitable truck to pull the diesel from -- a 91 one-ton 2wd Chevy with the 6.2 diesel. Anyone out there locally have any experience with this engine? I know the military uses it for everything, but you rarely hear of someone going from gas to diesel. The other way around, yeah. CK5 forums have a ton of info about this swap, but local knowledge is invaluable!

Also, any feedback how that diesel would work in my truck with 4.88 gears and a 700R4 Tranny? Thoughts?

-Ron

Post by **Yoda** » Wed Apr 25, 2007 10:16 am

heres a tought...hablas espanol?

bourban driver · Post by **bourban driver** » Wed Apr 25, 2007 10:52 am

Si -- mas y menos. Seriously, not enough to get by, but enough to trigger hysterical laughter among the locals. We were stumped in Santa Teresa last Christmas by a local surfer trying to explain the breaks to us -- we ended up drawing in the sand.

Website · Post by **Slinkey** » Wed Apr 25, 2007 11:47 am

bourban driver wrote:Si -- mas y menos. Seriously, not enough to get by, but enough to trigger hysterical laughter among the locals. We were stumped in Santa Teresa last Christmas by a local surfer trying to explain the breaks to us -- we ended up drawing in the sand.

mas o menos

Post by **hklvette** » Wed Apr 25, 2007 1:43 pm

Ron, depending on the size tires you have, the 6.2 will work with 4.88s, but understand that unless you put a turbo or twin-turbo setup on it, it won't have any balls whatsoever. If you can, pull then engine and trans as a unit, that way the trans is already set up for the diesel's redline.

Post by **BlueDodgeRam** » Wed Apr 25, 2007 1:46 pm

i thought the military used to use the 6.5L, but now have switched to the 6.6L D-Max.

Post by **hklvette** » Wed Apr 25, 2007 1:49 pm

BlueDodgeRam wrote:i thought the military used to use the 6.5L, but now have switched to the 6.6L D-Max.

That's true for the humvee, but the CUCV is a 6.2L The 6.5 didn't exist until about 1992/1993 IIRC

Post by **Leach** » Wed Apr 25, 2007 1:53 pm

I have owned a vehicle with the 6.2L diesel. With a single cab long bed 1 ton 4x4 truck it was ok, I wouldnt write home about it though. If you want a real diesel and worth the time/energy/money get yourself a 12V cummins. from around the 90's to 98 they had em. You will be happy as hell with that.

Post by **BlueDodgeRam** » Wed Apr 25, 2007 1:54 pm

Leach wrote: If you want a real diesel and worth the time/energy/money get yourself a 12V cummins. from around the 90's to 98 they had em. You will be happy as hell with that.

thats what i was thinking

bourban driver · Post by **bourban driver** » Wed Apr 25, 2007 4:31 pm

I'm looking for stone-cold reliability and parts availability in third-world countries over everything else. I'd install the banks sidewinder turbo system in it after freshening up the engine. I am planning to run a 37 - 38 inch tire (35's now), probably bias-ply so I can afford to take a couple of spares with me.

I know from experience that there are a lot of 6.2's left over from military apps and school buses wandering all over Mexico and Central America...I just wish they made more power.

Post by **hklvette** » Wed Apr 25, 2007 7:16 pm

You should be okay on 38s after the turbo, as long as your engine is running about 2k rpm in 4th at your normal cruising speed.

Post by **MtnToys** » Wed Apr 25, 2007 7:28 pm

Do you plan on doing some hardcore wheelin on this trip? A 37-38â€

Post by **Leach** » Fri Apr 27, 2007 9:21 pm

hklvette wrote:You should be okay on 38s after the turbo, as long as your engine is running about 2k rpm in 4th at your normal cruising speed.

Not with the 6.2L it is not worth its weight in poo. The turbo kits for that motor do nothing for it. Once again I owned a truck with this motor, military truck, and I wouldnt waste my time or money swapping that motor into anything, turbo or not. The motor can't handle it.

If you want reliability in the stone cold fashion I stand by my original statement of Cummins 12v. It is a turbo diesel motor and they will last forever.

Post by **hklvette** » Sat Apr 28, 2007 8:06 am

Leach wrote: Not with the 6.2L it is not worth its weight in poo. The turbo kits for that motor do nothing for it. Once again I owned a truck with this motor, military truck, and I wouldnt waste my time or money swapping that motor into anything, turbo or not. The motor can't handle it.

If you want reliability in the stone cold fashion I stand by my original statement of Cummins 12v. It is a turbo diesel motor and they will last forever.

For my own reference, are there any special parts that a 12V cummins swap requires to fit into an old GM fullsize?

Post by YJ » Sun Apr 29, 2007 1:28 am

I'm about as die hard a GM man as there is. That being said, the 6.2's & 6.5's are pretty much junk. One of my haulers (which I bought new) dropped it's 6.5 @ 50K miles. This truck was well maintained and taken care of from day one. I finally got GM to split it with me, but I still put about 2 grand into it and only after getting 50K miles out of it.

If you're dead set on taking a Suburban on this trip, you might consider finding one with the 6.2 or 6.5 already in it. Then swap the parts off of yours on to it. (lift, tires, etc.) I would think that this route would have to be quite a bit cheaper than doing a motor swap in your existing ride. Not to mention a lot more dependable. I've seen a few GM trucks with gas to diesel conversions and vice versa. Of those I've seen, none seemed very dependable and all had some issues. "Issues" of any sort is not something I would want on a trip you are talking about.

As far as the Cummins 12 Valve to GM truck. That would be a sweet set up, but one that I'd say would be very very pricey, and have a lot of snags to deal with to make it work.

I may be wrong, but I would bet money that in the end, you could go out and find a newer 2500 Sub with a Duramax and buy it for less than what you'll end up with in your current one doing the swap. Not to mention have a heck of a lot better, comfortable ride.

Just my $.02