Originally Posted by OVERTHETOP
I am swapping out a 1999 wrangler 4.0L engine and putting it into a 1999 wrangler that had a 2.5L. Are the transmissions the same or do i need to swap out the trans as well?
The 2.5L uses the smaller light-duty Aisin AX-5 transmission and the 4.0L uses the Aisin AX-15. You'll have to swap out the transmission as well as the ECM and engine wiring harness. The 4.0L can't even be mounted to the AX-5 for a short-term solution.