Hoping someone could clear some confusion on my part. My 2000 xj has consistantly low oil pressure (around 5psi hot idle, 20psi cruising) my ? is would just replacing the main bearings help and prolong the life of my 4.0 or do the cam bearings have to be replaced. If replacing the main bearings are not going to help than i will not replace them, but if it will give me a couple of years then i will do it, but if the only thing that will help the oil pressure is to replace the cam bearings then i will not fix it and just get rid of it. Anyone out there no the answer?