good to know... stickin' with 5k then!

 

Mobil 1 is indeed a Class III oil, not fully synthetic. I wouldn't worry about using it though, there's too many people that swear by it. I myself switched from mobil 1 to 5w-40 Shell Rotella T fully synthetic that is marketed to turbo diesel trucks. I also use it in my motorcycles and love it.

 

And yeah, 5k is a good oil change interval. If you want to pay like $20 per oil change you can send your oil in to Blackstone for an analysis and they will tell you if you can safely extend your intervals

 

Although the following article was written primarily for motorcycles, the vast majority applies just as well to cars and most is a detailed explaination of oil itself. It is a long read, but will likely tell you more than you knew there was to know. The primary difference is that in a motorcycle, engine oil also lubricates the clutch. Because auto oil includes some additives that can cause a motorcycle clutch to slip, it is important to only use motorcycle specific oil that does not have these additives.

http://motorcycleinfo.calsci.com/Oils1.html

 

Rotella T and Mobil 1 I love both and use the Mobil 1 Turbo Diesel truck in my car, and Rotella T 15-50 in the truck.... Rotella non-synthetic is prolly the best break in oil.