Many times fluids can be back wards compatible...BUT the original formula of Dexron 3 without the needed friction package isn't forward compatable.

YES as stated & posted many times the 722.6 fluid is based on Dexron 3 ATF! But the special friction modifiers that are added are required for long life.

And YES the fluid for the 722.9 trans is also Dexron 3 ATF. But again the additive package required for that trans ISN'T in the fluid that was developed for the 722.6 trans & isn't in regular Dexron 3.

IF you want the 722.6 trans to last 50K miles longer then use the correct fluid!

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