Air Bubbles in Transmission Fluid

[Nick Bruns]

Hi all.

I noticed last time I checked my auto trans fluid that it had bubbles on the dipstick. I hadn’t thought much about it, but after seeing the video hangout where there was a question about transmission shifting issues, Eric mentioned air bubbles in the fluid could potentially cause problems.

Well my transmission has had odd shifting problems for the last 2-1/2 years. I bought the car, drove it to the coast for my honeymoon, and it started acting up after the trip. It started having lifter noise as well. It revs until 3000 rpms before shifting from 1-2, and depending on how much gas I give it, the shift is like being shoved in the back or very firm if I put my foot into it. There is also some very slight but discernible slipping/stuttering in the 1-2nd change. This is only when it’s cold though. Once it warms up to temp it goes mostly away, but it still revs to 2500 rpm during the 2-3 gear change, and shifts abruptly (not really a smooth transition).

Could the air bubbles be related, or is my transmission on the way out? It needed a fluid change when I bought it (the fluid wasn’t really bad, but could be changed), but the issue happened before I did the 60K service (it had 70k when I got it, the car now has 103k miles). I just had another major service done on it in September to clear a CEL (I had asked a question about it on here) o2 sensor, fuel/air filter, plugs, plug wires, some belts.

If that’s the problem, how do you go about fixing it? BTW, it’s a 2002 Subaru Legacy GT.

Thanks!

Nick.

Topic

[Rereonehundred]

ATFs should have an anti-foamant present as bubbles are not good to have. Do aN ATF change to a good modern product which will presumably have the anti-foamant in it.

[Nick Bruns]

Thanks for the reply! Presumably they put in the OEM recommended fluid 3 years ago. If that’s the issue, I will change it when I get some $$$ for it (little broke right now).

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