Question

My 1998 dodge dakota 3.9L v-6 2wd, when I put in rear it shuts off.

Answer 1

Put the vehicle is gear and the engine shuts down, Do a throttle body cleaning, this can help the idle air control react better, Whe you put a load on the engine such as a gear change there a load on the engine to meet the engine demands the idle air control increases the RPM. If the problem still persist the idle air control valve replacement may just be the solution.