What are all these transmission oils ?! (ATF+4)

[Schulmann]

These days it is not easy to select a good transmission oil for a manual shifted car.
I just received my Viper magazine with a good article about transmission oil change.
Good it is perfectly clear I don't want to discuss it. But ... I have the opportunity to race another cars than the Viper.

So reads this:

Nearly all manual trannies run on 75w85 but certain guys run their trunny on ATF synth oil. In fact Tremec recommands to run certain of its T56 on regular synthetif ATF Dext III !

It seems that the ATF has a 5w30 wiscosity.

The Viper magazine talked about ATF+4 in the older Tremecs.

Help clearify things:


- What is the difference between ATF+4 and ATF III synth ?

- Why not to use ATF III synth in all Tremec T56 upto 2006 ?

 

[Johann]

ATF+4 is the synthetic, ATF+3 isn't. Both of these are formulated with friction modifiers for automatics with lockup converters, the friction modifiers might interfere with synchro operation in a manual trans.

Dexron III is just the third generation of Dexron fluid that's been around since the sixties, it isn't synthetic but some synthetics emulate its properties.