My '99 TJ 4.0 is getting close to 120k miles. About a month ago, I started getting some (what I believe to be) lifter noise. It was most noticable on start-up and when idling, however, when running, it seems to disappear (or the engine noise is too loud to continue to hear the lifter).
I have always run 10W-30 and tried to use some lucal additive to lessen the tapping. It didn't work. I had read on other forums to try using some heavier oil, so I swapped out my 10W-30 for 20W-50. I really haven't noticed any improvement in the tapping, however, now I am having some ignition issues. I have never has starting issues, but now it will take several tries to get her to turn over. I'm suspecting that this could be due to having a higher viscositivity (sp??) oil.
So, what would you guys do? Would you keep running 20W-50 and deal with the ignition issues, or drain it out and go back to 10W-30? What other additives could I try to reduce lifter noise? I don't want to have to get it rebuilt.
What's the worst that can happen if you run with a sticking lifter?
 - post title should have read Engine Oil Weight.