RE: adding oil to front & rear diffs improves power?
something like that. Also there should be a better grip to the ground, lessens tyre balloning, and is supposed to give these extras about handling and driving the car but to tell you the truth I noticed NO diffrence in mine and I still have a terrible problem with balloning tyres that I became laughing stock at my local track. Personally you havent changed them yet, dont bother for now, it just wont change the world