Really you can run anything from 5w-20 to 20w-50 in the jeep and it is really not going to care. So whatever you have laying around will work. Since your in cali you don't have to worry about your oil turning into molasses in the winter :P.
IF you were running a race motor then yes you need to choose your oil to what it will be required to do. IE I have a road race car- I ran 20w-50 in since I lived at high RPMs and lots and lots of heat thicker oil helps with that.
Know nothing SPEAK on everything
Originally Posted by ccain
Isn't the JK just a rebodied PT Cruiser?!
Originally Posted by coyote_94yj
Just a few more inches Red. You can take it.
If you haven't gotten more out of the insurance company than you deserve, then you haven't screwed them nearly as much as they have been screwing you for the past xx years.