castrol gtx 10w30 always, use to only use ac filters(they are bad now, so don't use them). car has 147,000 on speedo- but in reality has 200,000 miles. and had sat for 11 years, been running good since last year, un-opened motor. now i do add the zddp. i may try the blend, i've always used valvoline blend in my truck and now have 135,000 on it.
Mobil One 15w50..... Solid roller cam plus I want some film strength at 6500rpm:biggrin: I wish mobil one would show their PPM levels on zinc and stuff on their website. I had thought about using their 5w40 tubo diesel oil but I am not sure. I had always been curious about the ZDDPlus with a roller cam setup....sounds like it helps.
Ive used Mobil-1 10w30 full synthetic in my GN since the day I bought it two years ago. The previous owner used it so I saw no reason to change. Plus everyone says I cant anyway.
This most recent oil change I used my first bottle of ZDDP. Before that I ran 5 quarts of straight Mobil-1, and a PF-52 filter. Never had any problems.
I may switch to Mobil Delvac 15w40 if I can find it in quarts locally. Anyone absolutely sure is full synthetic? Noone around here seems to know for sure.