Transmission/TC Whirring Noise

[jwahl16]

1990 Legacy L
A/T 120,000 Miles

I have a whirring noise that comes from either my transmission, torque converter, or front differential. It usually occurs after the car heats up and while in drive. While moving it is louder than when it is stopped. I changed the fluid recently because the transmission jerks a little bit but did not drop the pan. Now the fluid has small bubbles in it even though the fluid level is within range (i checked properly many times). LegacyGT forums basically said it was on its way out but I am curious to know why with such few miles. Since this is a 1G specific forum maybe ya'll could provide more help.

Thanks in advance

[wtdash]

Hi,
Sounds just like my '90 Legacy @ about 140K miles, IIRC. It made a noise that another member on here diagnosed as the seals going bad internally - not something easily fixed.

When you changed the fluid, HOW did you do it? Just drain once or drain/fill/drive/repeat 3 times? Lots of fluid stays in the TC and so it takes @ least 3 drain/refill cycles to get the majority out. The whole transmission holds about 9 Quarts of tranny fluid and about 1.5 Quarts of front diff gear oil.

I do NOT recommend getting it flushed (after 100K miles) - Flushing can cause the seals to leak further. I lost reverse on my '95 4EAT after having it flushed to fix a torque bind issue...ended up getting it rebuilt.

EDIT:
I just read THIS post about flushing vs. just draining. I have to admit, if a flush does kill the transmission it probably wasn't in good shape b4 the flush anyway.

I'd also recommend substituting some of the Trans-X AT slip-stop & leak fix for tranny fluid. This stuff has helped others w/the 4EAT.

GL,
TD

[jwahl16]

I checked the dipstick for like the 5th time yesterday and it is now reading high, i must not of had the car hot enough or something stupid. I siphoned some fluid out so now it reads full, hopefully this will remedy the issue. If it persists i'll definitely take some more out and substitute in Trans-x since others have had luck with it. And to clarify i just drained it once, i know it was only 3-4 quarts and the system holds like 8.5. Maybe i'll repeat the process down the road abit. Thanks for all the help and i'll post back up if something pops up

[91Beater]

My tranny slips like hell after the fill/drain.

[Legacy777]

Welcome to the BBS.

Can you tell us the procedure you used to check the transmission fluid?

[jwahl16]

Thanks, and sure no problem.

Dive the car 15 minutes or so until it is good and hot. Park it, cycle through R,N,D a few times then leave it in park running. Then check the dipstick's "hot side." I believe that is the correct procedure.

[Legacy777]

Yeah that's pretty much correct. You should slowly cycle the gear lever from Park to 1 and then back to park. I don't think that would really affect things.

You may need a little more time than 15 minutes to get the trans up to normal operating temperature though. Again, I don't think that would cause the issues you're seeing though.

[jwahl16]

yeah, it seems like i ran it too long overfull. I drained about a quart out so it now sits 1/3 of the way between low and high but there are still bubbles on the dipstick. I used some trans-x as well but it did not seem to help much.