Three monthes ago I purchased a 99 cherokee 4x4 with the 4.0L. I have always wanted to lift up a jeep (this is my second cherokee, but the first with 4x4) and now I think might be my chance.

The engine is making a knocking sound when I accelerate. So I assume that I might have to do work on it before I put to much into the suspension. Does anyone know what that knocking sound is? Im not really a mechanic. It has 150000 miles on it. Should I just get a crate motor, or start think about rebuilding. I really wouldnt mind more power before I get it truely offroad ready.
Also I want to do 31's or 33's with a little lift, I was thinking about 3 or four inches. Again I am not a mechanic so Im not even sure if that can work. What should I be looking for?
Im pretty sure that I am going to get good deals on parts (cost +10%) so I just need to know what I should be looking for. Anyone got any ideas?

 

Is only knocking when you exccelerate?if so it could be the flexplate,it could be cracked or the bolts could be loose,bearing knock will be there all the time,150,000 is not many miles.

 

Is it possible to replace or fix something like that? Also, any ideas on getting more power out of it? The acceleration is slow. Would that be fixed by fixing the flewplate? I only hear it when I accelerate, but I guess that doesnt necesarrily mean that it isnt there.

Anyone know what kind of steering stabilizers to get when I purchase the lift kit. I recently learned I would have to trim the fenders to go above 31 so Ive decided to stay at 31