Castrol "DEX/MERC" atf ok for gm 4l60e?

[BayouTodd]

Went to walmart to get a few things and remembered I needed 6 qts of Dex III for my 4l60 fluid drain. After looking for a few moments, I discovered walmart (mine anyway) only carries two brands of DEX atf: Supertech (their generic brand) and Castrol "Dec/Merc" which is described for both gm and ford cars. Is this OK to use in my 4l60e? Or should I get the Castrol Dex VI which is SYN...?

 

[The Critic]

That fluid would work, but the new GM Dexron-VI is the best choice.

 

[Nick R]

Dexron VI is definitely the best option.

 

[BayouTodd]

So if I go with thr Dex VI and I dont know whats in my tranny now, will it be ok to mix Dex VI (syn) with whatever is in there?

 

[Nick R]

Yes. What you have in there will be either a Dex III, Dex/Merc, or already Dex VI and there shouldn't be any concern about mixing.

 

[BayouTodd]

Did the drain and filter, added the ST Dex VI...thanks.

 

[Kaboomba]

Congrats on your new simple, yet genuine performance upgrade: synthetic Dex VI