Mobil1 is all that I ran in my H/C L33. It would see 7000rpm numerous times a day and had 180k on it. The motor is now in my brothers 92.
Since I put my 6L in I have been using Rotella T, only have a couple thousand km on the new setup so time will tell
I use it in all my vehicles and have never had a problem with it. Where I work ALL of the lubricants are Mobil synthetic's and if their product is what NASA specs for its machines it's good enough for mine.
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