i realize changing my gas Isuzu rodeo to diesel is not easy, only looking for what size motor will do ?

Answer 1

Isuzu makes diesel engines now for box trucks in their vehicle lines. Some of the older pup trucks came standard with a diesel engine in them. They now Build several including the Duramax but they have one out called the 6DE1 3.0 liter that would probably push your Rodeo pretty well. It wouldn't by any means be a race car, but it would run decent.