Could a Cummins 5.9 engine fit in an M-body Chrysler?
The Cummins is a great engine, but it weighs more than twice what a small block Mopar does. I don’t think it would fit, but even if it is possible, the cost and weight would make this an unpleasant combination. You’d still need to fabricate the engine mounts, have some serious electronics expertise to get the ECU to work, and spend a fortune, but the Mercedes diesel out of an early Sprinter van would probably make for a better driving and more efficient swap. The 4 cyllinder out of a Jeep Liberty diesel would also be a better fit, if you can find one. Good luck. Whatever way you go, a diesel Gran Fury would be an interesting creation. It will be a hell of a project though, by the time you get the electronics and fuel system sorted out.
