Transmission flush GM fluid type

[Paul R]

It’s time to flush the fluid on my wife’s 2003 Bonneville SSEi. Dextron 3 or 6?
Dex 6 I think would be better. Any opinions?

Topic

[Jared Thomson]

You should look in the owners manual of the vehicle. It will tell you the manufacturers reccomended transmission fluid type.

[Paul R]

In 2003 only GM fluid was dextron 3. Dextron 6 is supposed to be backward compatible. I was wondering if anyone knows for sure if it’s better in an older car built with dextron 3.

Does it really mix or is GM just consolidating inventory to stock only dex 6?

[Roy French]

Dex 6 is what you want to use. It is backward compatible, and a much better product. It does cost more though.

[Shaun_300]

Yep, use the Dexron 6 in any older Hydramatics that called for Dexron 3.

[Author]

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