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Can 2QTS too much ATF damage auto trans?

Will overfilling damage auto trans – was told my auto trans was 2 1/2 Qts overfilled!!! ps. It was rebuilt after 108K!!!

You didn’t say what model Hudson you drive but it could cause trouble. A quart ove is ok but two qts might flood the drums and cause frothing and air in the pump.
Be sure and measure the level yourself as it’s hard to read on some cars.

The theory is if the ATF is oveerfilled it will foam and not lubricate as designed. It will cause premature wear and eventually failure. Did this happen to you? I am sure there is some factor of safety built into overfilling but 2 qts seems like alot. If it is performing well you are probaly ok,but you don’t realy know if you took some life away from it. Just drive it and note how it is performing.

I would keep an eye on the level and observe if the fluid on the dip stick looks dark, has solid particulate in it or smells unusuall.

I have read some recomend over filling certain types of transmissions by 1/2 to 1 qt and feel it will keep it running cooler and performing well on sharp cornering…they feel it will not cause a foaming issue. This is anecdotal and has been posted on other boards by people who supposedly know the bisiness. I would not do it with out realy know it was from a reliable source.

Overfilling an automatic is just as bad as underfilling it. When overfilled, the internals churn up the fluid causing air bubbles. Automatic transmissions rely on hydraulics to operate properly. Air in the hydraulic system will cause the clutches and bands to slip which creates excess heat and destroys the transmission. 2 Quarts overfilled??? It can make a difference depending on the type of vehicle.


2001 SATURN SC2 – will 2Q over ATF destroy trans??