hi all. i am thinking about change my motor oil,transmisson fuild and diff oil to royal purple on my next oil change..i went to there site and the have alot and i mean alot of differnt magazines and companys that have reviewed this stuff and the all seem to find a horsepower and mpg benifit by using it.. and dyno test also .what are ur guys thoughts on this stuff http://www.royalpurple.com/ check out there web site and tell me what u think ... thanks all

 

Is your car out of warranty and do you feel like experimenting? I tried RP in my M3's tranny - it was better than BMW's LT1, but as soon as they came out with LT2, the dealer put that in under warranty and it was much better.

With the 997S, I would never experiment with non-approved fluids in the car, especially when the car is under warranty. Mobil 1 is well known as a great synthetic motor oil. I don't know what they put in the tranny and diffy and don't care - it's held up wonderfully to 5 track days so far.

 

I've try Royalpurple on my previous 993 and didn't feel any different, I never try it on the tranny so no comment on that part.
the color of the oil is actually purple so it's hard to verify if the oil degraded or not after few k miles. I later went back to Mobil1 and still couldn't fell the different.