Royal Purple stuff causing blown engines & tranny failur

[Jeff]

Go back to the OEM stuff. It has friction modifiers that prevent what the PM said would happen. This is the same with Mopar transmissions and LSDs on trucks. For truck LSDs we actually have a separate bottle (only an ounce or so) that says "friction modifier: for use with Mopar synthetic differential fluid". I read a lot about this kind of thing when I was researching want oil to use in my manual transmission. I'm using regular dino 10w30 because M1 has caused failures.