The 5.2, from what I've learned, is arguably the ideal motor to swap into the TJ. The computers talk, the gauges listen, the emission system is the same, you can use the factory auto shifter, etc. You'll need a new radiator, throttle cable, motor mounts, electric fan (not mandatory, but preferable), and the tranny mount will have to be fabricated.
BackwoodsOffroad.com has all the parts necessary for the swap, and can mate the engine harness with the body harness.
The ZJ 5.2 is the same as used in Dodge Dakota, Ram 1500, and Durango, so those make good donors, as well. The 5.9 works, too. I plan the same swap as soon as the right wreck comes available.
Last edited by ToyTJ; 02-15-2008 at 03:33 PM..