Looking at buying a Square with Dodge guts...

[playinsafe44]

I'm talking with a guy regarding his square body chevy that has a 6BT in it that he wants to sell. Right now I'm very interested, but I don't know a lot about the cummins engines. He says the 6BT was swapped into the truck in 1990 (1st gen?) and only has 90,000 on the engine. It has a TH400 and he says it has a NP203. There are a few things I'm not sure about.

1. The intake crossover pipe looks different. Is this a industrial application?
2. It still has vacuum brakes. I thought there wasn't enough vacuum to run these, and that's why everyone goes with the hydroboost swap.
3. He claims it's an NP203 (fulltime 4WD), but he said the shift pattern is 4H.4L.N.2H.2L. He also says he has new milemarker hubs for it. Is this an NP205?
4. This is not an intercooled engine. Can it still be upgraded like the rest of the 6BT engines? I think I would want to bump the power for towing, and try any mods for increased MPG.

The price seems reasonable, but I don't want to buy a lemon without knowing what to look for.

[Dieselwrencher]

Originally Posted by playinsafe44

I'm talking with a guy regarding his square body chevy that has a 6BT in it that he wants to sell. Right now I'm very interested, but I don't know a lot about the cummins engines. He says the 6BT was swapped into the truck in 1990 (1st gen?) and only has 90,000 on the engine. It has a TH400 and he says it has a NP203. There are a few things I'm not sure about.

1. The intake crossover pipe looks different. Is this a industrial application?
2. It still has vacuum brakes. I thought there wasn't enough vacuum to run these, and that's why everyone goes with the hydroboost swap.
3. He claims it's an NP203 (fulltime 4WD), but he said the shift pattern is 4H.4L.N.2H.2L. He also says he has new milemarker hubs for it. Is this an NP205?
4. This is not an intercooled engine. Can it still be upgraded like the rest of the 6BT engines? I think I would want to bump the power for towing, and try any mods for increased MPG.

The price seems reasonable, but I don't want to buy a lemon without knowing what to look for.

I'll try to help you out with as much as I can from the top of my head.

1. The intake crossover is definitely not from a Dodge application. From the looks of the turbo location, this looks like a set up from a bus. Meaning the engine could have came from a bus. The engine can still be upgraded also.

2. If the truck has vacuum brakes it will be okay as long as they used the vacuum pump/ps pump that the dodge cummins trucks had. If you want to tow heavy, a hydraboost set up would suit the job better.

3. on the tcase, I'd always thought a NP203 had no 2L unless the tcase has had a part time conversion kit put in it.

4. The non intercooled engines are still a great platform to upgrade. They actually have a better piston design with a bigger fuel mixture bowl and can take a few different injector spray angles compared to an intercooled engine. You can still intercool it as well if you choose to.

My only concern would be the TH400. These take a lot of good parts and a good torque converter to live behind a Cummins. If you will be doing light towing and not over 250hp it should last. Anything above that and you'll be replacing trans parts. Good luck with your choice.