“I was having horrible drivetrain clunking problems when braking and accelerating in my ’97 Yukon 4WD caused by a binding slip yoke. I was told the only fix was to remove the yoke and apply special GM grease to the splines. This fix would last about 300 miles until the atf in the transfer case would wash the grease away.

I replaced the (fresh) atf in the transfer case with your Synchromax and after four miles like magic the clunking stopped. Literally thousands of GM trucks and SUVs have this problem and GM has issued service bulletins saying it is ‘normal’. I hope you guys can get the word out that your product can end this problem easily and economically.”

—Richard Harmier, customer

“Tyler Smulders (5th at Loretta in 2004 open class) is hooked on RP Synchromax. He said after running the oil: ‘This is the first time ever my clutch hasn’t slipped on my Honda CRF250’.”

—Carl, Virtually Real Motorcross