Jeepcrush4
NAXJA Forum User
- Location
- Flushing new York
I just bought a 1997 cherokee 4.0 and was in the process if doing an oil change. The engine was rebuilt by the second previous owner and was a liitle over 100k miles. I understand the idea of synthetic oil loosening gunk and varnish possibly causing blockage, but I've always had success with valvoline 10w30 synthetic. I've read that some experienced issues on going synthetic with high mile 4.0 engines. Some recommended havoline 10w40 while others said generic. I'll go with the consensus. Avoid synthetic? Any particular brand and weight? No oil leaks thus far.