Hi I have a cutlass supreme with a 350 and turbo 350 trans (i believe so). The stock owner manual asks for DEXRON ATF for the fluid, but in the 70s it's the DEXRON II time. I saw mobile has DEXRON VI, will that work? Is it going to harm the trans or be beneficial for it since it's newer oil?

 

You won't harm anything. I typically use whatever is the cheapest Dexron compatible fluid from the local auto parts store.

 

Most ATF are backwards compatible.

 

Anything that says "Dexron" on it should be fine.

- Eric

 

You can still find dexron III. The dexron VI is synthetic. It won't harm anything to mix them, its just that the dexron VI costs more.

 

If you read the back of the bottle, it will say, to use in 2006and older, or the newer one says, for 2006,and newer. You want the one for the older. I think the newer one is sympathetic?

 

Yes the DEXRON VI is synthetic

 

I wouldn't recommend mixing synthetic Dex with standard Dex. Stick with standard dyno juice Dextron in this case.

 

Sorry Dr....pet peeve.
There is no T in Dexron.