Is it possible for engine oil mix with transmission fluid ? If so how to check it ? The fluid is getting foamy after diving for longer time at higher speeds , and transmission gears are slipping. I had the symptoms before , after changing ( last summer ) trans. filter and fluid everything was fine for 6 months .
Not unless someone poured engine oil in the transmission.
However, it IS possible for coolant to mix with the transmission fluid if the transmission oil cooler inside the radiator develos a leak.
Sounds like either an internal air leak, overfilling (allowing the gears to whip the fluid to foam), contamination, or very poor transmission fluid that doesn't have good anti-foaming additives.
Since it started after a fluid/filter change, I'd repeat that operation making sure that the filter is fully seated on the bottom of the transmission valve body to preclude an air leak there. Also, your
3-speed autimatic doesn't strictly demand ATF+4, but its just about the best fluid on the market right now from a longevity point of view (oxidation and viscosity stability). I'd use it.
While the pan's off, inspect for gritty sandy residue which would indicate a coolant leak into the transmission oil. When that happens, you almost always get the reverse as well, so check the radiator for brown gritty scum floating on the coolant.
Another thought- you might check for a BLOCKED tranny oil cooler. Overheating fluid can sometimes foam also.
Also make sure the right filter is used - on some Chrysler trannies, the dealers are known for selling you the wrong filter - they look exactly the same - except the nipple is shorter and doesn't mate up with the valve body. I was warned about that here, and darn if when I got a filter from the dealer a couple of months later, that's exactly what happened - fortunately, thanks to the warning here, I noticed the problem vefore buttoning it back up.
Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
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