Thread: Another fluid flush?!

Originally Posted by rick130

You mustn't too much hard off-roading, it's dead easy to overheat PAS fluid in slow, hard, full lock/lock to lock stuff. (as it can in high speed stuff too)

Well thats probably why mine is black, lots of offroading. Lol

Dex II and III are no longer a 'spec', ie. GM have revoked all licences and they've all been replaced by Dex VI which is backwards compatible.
As Jon said, all the Dexron fluids are backwards compatible, GM was very concious of achieving that.
FWIW I don't think there's much difference in actual viscosities either, there'd be a bigger variation between batches of the same fluid.

Having said that re the licences, there are heaps of fluids that meet the old specs, and a Dex III type fluid is fine, it's just a later specification than a Dex II.

IME a dedicated PAS fluid like that used in later Disco II's, Deefers, (eg. PAS 14315) etc is a nicer fluid in use, much less to no noise, groan, etc.
Of the couple of ATF's I've found to give a similar performance is Castrol's high performance Transmax Z, the straight Dex IIIH fluids I used were pretty ordinary after using the Land Rover/Caltex PAS fluid. The noise and feel left a lot to be desired.