Accidentely put 1 qt of oil in my transmission -ford windstar?

Accidentely put 1 qt of oil in my transmission -ford windstar?

Oil will swell your seals and wreck the transmission. Flush and replace the fluid.

Hi so time to check on how much is needed.

Drain and flush your transmission and do a back-flush of the transmission cooler (part of the radiator). Replace the main transmission filter, and the thimble filter. After filled with new fluid run it up to temperature and **** through all gears twice. Shut it off and drain and fill it again. This time add a bottle of Lucas Transmission Oil Treatment. You could do less than this, but this is what a pro would do for a trans oil contamination. They cost thousands to overhaul. Up to you…

Don't! Drive it till you know its flushed clean

Don't drive - drain. As cimra says, can swell seals… And since the oil is much thicker than transmission fluid, hard on pumps and the extra pressure also kills seals.

These transmissions hate to be over filled so don't drive it long distance, there's nothing in 5W-20 oil that's going to cause damage… Get the transmission serviced at a Ford dealer, the Rotunda flush machine has the correct pressure for this. We did testing for Ford during the development of this transaxle and Ford engineering determined flushing is preferred way to service. The filter isn't affected by engine oil so unless it's just time, flushing is fine,… These Ford transaxles do not like to be over filled or under filled… That's your main issue…
I've ran engine oil/atf mixtures in transmissions of street/strip cars for decades my transmission man recommended it…
EDIT: if you haven't started it… Just remove the transmission pan like you do to service it let the oil and atf mixture drain out, replace pan, the transaxle should have the Ford reuseable gasket. You need to buy 4 Quarts of MerconV only add enough to bring the level to the MAX level…

In an automatic, that can destroy the clutches and quickly. If you have not started it, drop the pan and change the fluid and filter. If you have started it, you may be out of luck. The trans has a series of clutches and those will absorb the oil. This makes for a slipping issue.

Its ruined. You're gonna need it rebuilt or find one from a junkyard

What year is it? That can tell you what goes in it.
Did you start it?
Do you have AAA?
The mess you are going to make, and the fluid you are going to buy makes it worth having the trans experts tell you exactly what to do and get them to do it.

No spills, no extra quarts, they sell ATF in bulk.
They can offer you a coupon, there are many ways they can get your dipstick out of the wringer.

Call them and do not start the engine.