Dexron

I had a brand X front wheel drive car that were know for trans failures. So I changed the ATF once a year, the trans is still working fine.

and don’t just pump it out the cooler lines, remove the pan and clean it out. Have you ever noticed that gray film inside a trans pan? Isn’t that contaminating it? Yes can/will/does.

For those who say they don’t get contaminated, have you ever taken some apart and looked in all the “corners” of the trans and see what kind of crap “can” accumulate in there?

bottom line is change the fluid and drain the converter.