I have a good 5.9 gas motor and tranny out of a 98' 4x2 body. Then I have a buddy selling this 99' 4x4 1500 ram but the truck has 237,000 miles and the tranny won't shift out of 1st. Was wondering if it would be possible just swap out the motor and tranny and replace them with the ones I have.

 

Nope. Too many differences between the two. Unless you just want a 2wd truck.... even then, you will probably have troubles with driveshaft length. Little bit of troubleshooting on the 99 might turn out to be an easy fix though.

 

Unless you take the 99 body and put it on the 98 engine/trans/frame.