Synth auto trans fluid?

[RollingThunder]

Originally Posted by LankyTim

If you put fully synthetic in the auto box, does that mean it wont need changing ever again?

I wouldn't say that to be honest - it won't degrade as fast as dino based stuff, and will put up with more abuse (eg higher bhp= higher autobox pump/valve stresses and temperature), but I'd still be tempted to change it every 60k or so (can't remember what the recommended change interval is at the moment).

[amsoil]

Originally Posted by RollingThunder

I wouldn't say that to be honest - it won't degrade as fast as dino based stuff, and will put up with more abuse (eg higher bhp= higher autobox pump/valve stresses and temperature), but I'd still be tempted to change it every 60k or so (can't remember what the recommended change interval is at the moment).

Totally agree with the above; having said that I know that Performance Oils have never knowingly supplied ATF to replace synthetic ATF. (but it surely must happen one day) I know the Amsoil ATF take 100 degrees more heat and survived 3 times longer than it took mineral ATF to break down under test. What wasn't clear from the tests is that at 3 times what it took for mineral ATF to fail they stopped the test. They didn't stop the test because the Amsoil ATF had failed. (guess they just got bored or had proved the point.)