1st Gen Crew Cab Engine

In 92 I put an 89 Cummins engine with an automatic overdrive trans into my 75 Dodge B300 van, replacing the 360 it had. I also swapped the 4:10 gears out for a 3:54 set.

It was a lot of work and not cheap but the day we crossed the Rocky Mt. towing a car headed west toward Bonneville without having to shift out of overdrive made the 6 months of work worthwhile. I had made the same trip with the 360 and it worked a lot harder, especially because of gaining altitude which didn't faze the diesel.

With the 360, the van always got 9-11 mpg no matter what you were doing with it. With the diesel it always got at least 15 even driving aggressively. On the road at 70 mph it would do 22-23 empty, 17-19 towing.

Yes, it is noisy. One of the big sources of noise on the early engines is the mechanical injector pump. Keeping the lifters properly adjusted helps too.

If you do this you need to get the entire underhood wiring harness, along with the radiator and trans cooler. Also the driveshaft, which has really big U-joints.

If you want to keep this truck for a long time like you say, save up your money and do this, you won't regret it. The improved performance and mileage over a gas engine is incredible.

Gary