Great info, thanks. I am looking hard at the Amsoil signature 0w-20, I can pick it up at a good price through a friend who is an amsoil dealer. Any recommendations for or against? How about you just tell me what to do, eh? I figured since you have done all of this research, you are using the best in your "sick intentions" car. LOL
Edit: I guess we posted at the same time. Thanks for all of your help.
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First of all, with 15,000 miles on that tranny I'd get that changed right away. But for the motor oil I'm not sure it matters which brand..as they all have to meet API regulations. (Except Amsoil... oddly enough, they don't like paying for the API license)
If you don't mind being a Guinea Pig why don't you try the following:
1. Pick up 5 qts of WalMart generic 5w-20.... or whatever regular oil you want. Drive for 4,000 - 5,000 miles.
2. Send in a lab sample. Now you have your baseline.... and the minimum you should expect.
Now let's see if spending more gets you more... because for many drivers i'm not sure it does.
3. Repeat with Amsoil Signature Series 0w-20. Change after 6,000 miles and test. Do wear metals decline? Does the oil last longer (oxidation, TBN, etc) Does fuel economy and/or power increase?
4. Repeat #3 and run for 8,000 miles. Or go to 8,000 immediately if driving longer distances.
5. Repeat and run for 10,000 miles (and beyond) or until the lab results dictate otherwise.... but no more than 25,000 miles in a single year. Keep in mind filters need to still be changed according to their own lifespan. Even Amsoil filters are only rated to 15,000 miles for the SI.
The Blackstone technicians will often provide an actual recommendation based on your test results.
Alternatives to Amsoil. Pennzoil has their new "ultra" synthetic which looks promising. Very limited deposit formation. Liqui Moly (some call it LM) has their state of the art "Longlife PLUS"... about $15.00/qt. Outstanding oil. On the super affordable end -- Mobil 1 is fine... but wouldn't recommend it for more than 5,000 (7,500 MAX) miles. But it's dirt cheap, often on sale at Costco for $4.50/qt... i.e., about $26.00 for 6. I use M1 for 3,000 miles... and no more than 5,000 MAX in the family car. But that's just me. Test results indicate most drivers can use it longer.