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Mickeyfan0805's avatar
Mickeyfan0805
Explorer
Jul 22, 2013

Adding ATF when you don't know what's in there

We had our transmission fluid flushed and replaced last spring and, being the non-mechanical idiot that I am, I didn't ask for detail as to what they filled it with. Since I didn't ask for synthetic,...
Tow Vehicles
mapguy's avatar
mapguy
Explorer
Jul 22, 2013
The Dexron iii vs Dexron VI serial number break is in mid-year 2006. GM does not acknowledge that transmissions built before the serial number break are at risk for seal hardening. Best way to protect yourself is to use Allison spec fluids. TES-389(Standard duty) or TES-295 (Extended duty) spec fluids. Change the spin on filter @ a max of 25k intervals.

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