New Subaru Owner, Strange transmission noise.

[hitchhykova]

A friend of mine completely sold me on Subaru, so I went out and located my self a FWD 1991 Subaru Legacy LSi with 170,000 miles. It has the 2.2L N/A with the 4EAT Autotragic.

Other than a mysterious oil leak (Oil seperator plate?), everything on it is perfect for what I was looking for.

I flushed out the transmission and replaced the fluid with new ATF in the first couple days of owning it. About 2 weeks have past now, and I do a lot of long drives with it. It takes to the long drives perfectly, but sometimes, the transmission starts to make this whirring sound under heavy load. If I back off the gas a little, the noise goes away, I mostly hear it between 3rd and 4th.

It shifts as it's supposed to, no hard shifting, no slipping, no crap in the ATF. I can only get it to make the sound once in awhile, I beat on it a little earlier, and nothing, I couldn't get it to make the sound again.

I read though several posts with people having an issue that sounded like what I get from it sometimes, but no real definitive answer.

Anyone actually know what the sorce of the noise is?

[Legacy777]

Welcome to the BBS.

I'm afraid I'm not of much help on the noise. Does it vary pitch at all with engine speed, or just with engine load?

[wtdash]

I had a similar issue on my '90 4EAT (before the turbo swap). Any load on the tranny and it made a 'whirring' noise...shifted fine - no other issues.

I was told by another Subie owner it was likely the internal seals....but not confirmed by a mechanic.

I replaced the tranny before it actually failed, but it never got worse in 5K miles.

Also, you're likely correct in the 'rear separator plate' leaking. Pretty common as Subaru has gone a thru a few revisions of that part - plastic & aluminum. You'll have to pull the engine/tranny to fix it.

[hitchhykova]

Yeah. It was doing it under load. I checked a few times and found the transmission to have been overfilled by almost 2 quarts. I drained it back out and added in 5 clean fresh quarts, and it seems to be the magic amount the transmission wanted.

I can't really recreate the noise now, when I hear a hinkling of it, it's not NEARLY as loud.

Only thing I can detect now is a slightly slow shift from 2nd to 3rd until it's warmed up. If I read correctly, that's normal on old 4EATs


Also... Our 4EAT transmissions, are they almost the same as the F-4EAT that Ford and such used??

[hitchhykova]

I had a similar issue on my '90 4EAT (before the turbo swap). Any load on the tranny and it made a 'whirring' noise...shifted fine - no other issues.

I was told by another Subie owner it was likely the internal seals....but not confirmed by a mechanic.

I replaced the tranny before it actually failed, but it never got worse in 5K miles.

Also, you're likely correct in the 'rear separator plate' leaking. Pretty common as Subaru has gone a thru a few revisions of that part - plastic & aluminum. You'll have to pull the engine/tranny to fix it.

As for that plate, I can see it though a hole on the top of the engine, I think it's the inspection hole for the TC, but I can see I have the aluminum one. The leak is not that bad, if it gets worse I'll pull the engine (I'm a former Saturn mechanic, yay economy!) and just do all new seals on the backside of the engine along with that leaking plate. In over 1700 miles I've lost less than a quarter of a quart.