so i got a 99 WJ that has a blown motor and at first i was going to rebuild it till i found out the cost of a rebuild kit is anywhere from 600-1200 so now im just looking to pick up a junk yard motor and save myself alot of work..its a 4.7. can i get a 4.7 HO out of a 01+ wj ? im planning on whatever motor i get taking the whole wiring harness and ECU with it. is this possible? what kinda problems am i going to run into?

this is something we might> have better lucking finding on MC.. id like to know more about swapping an AW4 into my '04 4.0HO...

The main differences between the H.O. and the standard 4.7 are the internals and the intake manifold. The size of the engine doesn't change, and if your taking the PCM and wiring, it should just be able to drop in. There are a few more sensors and whatnot along with a different PCM flash therefore making the wiring harness a necessity to grab.

Main differences between the two -> http://www.wjjeeps.com/ho_engine.htm#DIFFERENCES

ZJipsomatic, the AW4 is OBDI, so theres that whole mess to deal with. Theres a writeup on jeepforum.com about swapping an AW4 into an OBDII ZJ. Considering you'd most likely run into similar problems, it might be worth a read.

well my main concern wasnt so much between the 4.7 and the 4.7 HO but more with the 99 4.7 and for example a 04 4.7..i just want to know that so long as i take the ecu and wiring harness and swapp it all out i should be good.

When i blew my 4.7 in my 00 WJ i was gunna drop in a 5.7 hemi. The only difference in them two was the motor mounts and the computer. I ended up just rebuilding the 4.7 but not to sure how long its going to last.

how much did your rebuild run you?

It was about 800 and we did the work ourselves.