I had this tacked into a different thread, but I think it may be lost there.

 

Last week I noticed that my front differential oil level was low, so I topped it off, and in doing so over filled it. I don't know the amount of fluid that the dipstick measures between the filled line and the low line, but I probably only put in half a bottle of gear oil. Anyway, I took the car on a 60 mile trip Friday night where I was hitting 70 at some times. When I got partway there I saw smoke coming from the back of the car and smelled what I thought was gear oil. At my destination I saw that there was fluid dripping off the exhaust system. I couldn't get under the car and had no time to try to do more with it. I drove it home, and the smoking and leaking continued.

 

 

Today we drove the car to church in an effort to maybe burn off the oil and see what was going on. 10 mile trip both ways. On the way home, the car stalled at the stop sign, which is weird. As we are driving, the smoke is continuing. I got it home, and decided to check to see if the diff. oil level was lower now. NO, it was NOT. It was still over the Full mark. Then I checked the AT fluid level. It was below the the end of the dipstick. I put in 1.5 quarts with the engine running, but it still wasn't up to full. I decide to pull the car into the garage, and see a trail of ATF fluid behind the car into the garage. A big puddle of ATF was on the ground where the car was.

 

So it looks like there is some major leaking going on of the transmission, and I don't know why the differential still shows more than full, when I assumed that it was leaking differential oil on my first trip.

 

Tonight I put it up on jackstands and I think that the fluid is coming out of the seal at the back end of the transmission right at the driveshaft.

 

So, would replacing that seal and draining some differential oil fix this, or could that front trans seal be a problem? I really don't understand how that front seal leaks. It would be a blessing if it is just the rear transmission seal. It's hard to imagine how a seal could just start letting ATF fluid run out so easily.

 

I would appreciate any comments from you guys who know this stuff so well. Thanks!

 

Oh, this was the car that was stalling when put into gear on real cold days...not sure if that is fixed or not, but it might be.

Edited February 13, 201214 yr by LeolaPA

It sounds like maybe you should have an expert look at the car, maybe someone else on the board familiar with your model car can come check it out and fill you in on some stuff.

If you diff oil hasn't changed level, an the oil hasn't discoloured that means it's not getting ATF leaking into it.

The diff level has nothing to do with the ATF level as long as the seal doesn't leak. Not sure why that's surprising you.

 

Can you pinpoint where the ATF is leaking from?

The first thing I'd check is the cooler lines to the radiator. There are a few pieces of hose. So you have a bunch of hose clamps and hose that can get old and cracked.

If you diff oil hasn't changed level, an the oil hasn't discoloured that means it's not getting ATF leaking into it.

The diff level has nothing to do with the ATF level as long as the seal doesn't leak. Not sure why that's surprising you.

 

Can you pinpoint where the ATF is leaking from?

The first thing I'd check is the cooler lines to the radiator. There are a few pieces of hose. So you have a bunch of hose clamps and hose that can get old and cracked.

 

The diff oil is just a light brown color. I can't say for certain that there is no ATF in it, but it doesn't look bad.

 

The ATF I think is coming from the back end of the trans (right where the driveshaft come out.) I DID check the cooler lines and did not see any problem there. There is fluid slung above the location where it seems to be coming from, so it looks like it is coming out and getting whipped by the driveshaft on the underside of the car.

The diff oil is just a light brown color. I can't say for certain that there is no ATF in it, but it doesn't look bad.

 

The ATF I think is coming from the back end of the trans (right where the driveshaft come out.) I DID check the cooler lines and did not see any problem there. There is fluid slung above the location where it seems to be coming from, so it looks like it is coming out and getting whipped by the driveshaft on the underside of the car.

 

I'd start by cleaning the underside up really well so there isn't oil all over the place.

Then let it run for a bit without driving it. If it's leaking that badly, it should leak while idling, or holding it at cruising RPMs.

 

While you're driving all the fluid that's leaking is blowing down to the back of the transmission and making a really big mess.

If you start with a clean transmission it will be easier to pinpoint the leak.

It sounds like maybe you should have an expert look at the car, maybe someone else on the board familiar with your model car can come check it out and fill you in on some stuff.

 

I'm in Leola, PA, just east of Lancaster PA. If anybody is in this area, I'd be glad to have them look at it.

 

If I get enough reassurance that this is just the back oil seal, I will take it to my local guy to get it replaced.

 

So can overfilling the differential somehow blow out the back seal?

I'd start by cleaning the underside up really well so there isn't oil all over the place.

Then let it run for a bit without driving it. If it's leaking that badly, it should leak while idling, or holding it at cruising RPMs.

 

While you're driving all the fluid that's leaking is blowing down to the back of the transmission and making a really big mess.

If you start with a clean transmission it will be easier to pinpoint the leak.[/quote

 

I have the car on jackstands in the front, so I think if it warms up tomorrow I will start it and get under it and look. I think I'll do that without cleaning it at first, and if is obviously at the rear of the trans, get it all clean after it is fixed.

ATF can leak out the bottom of the ATF dipstick tube; there is a oring there at the trans housing, that gets brittle and old and leaks, have had that on 2 of mine before.

 

it then drips back to the tailshaft where it drips down.

 

 

that would be my guess.

Just checked this.

Had wife start car while I watched the back end of the trans. After 10-15 seconds fluid started flowing out of the back of the trans at the driveshaft.

 

So, if I replace the rear seal, will it fix this?

Local Subaru mechanic says that the rear housing needs to come off, and that if there is too much movement in the driveshaft that there might be something worn (?) back there that might require replacement of that housing.

 

It is leaking with the car just sitting and the motor running, that's why he came up with this hypothesis.

The seal can't be very expensive, what do you have to loose by replacing it?

Never know, it might work.

Since that back housing has to come off, local Subaru guy quotes $350, including replacing the back housing if it somehow is bad (?)

 

Before I realized the back housing had to come off, I was going to have my general mechanic do it. That would have been only $45/hr.

 

This car has been such a headache, that I'm toying with just putting it on Craigslist AS-IS and letting it go. I just bought my daughter another one, and it seems to be in good shape.

This car has been such a headache, that I'm toying with just putting it on Craigslist AS-IS and letting it go.

 

What is the car--year, model, tranny, mileage? Maybe someone on USMB might want to make you an offer!

It's a 95 Subaru Legacy LSi. Dark Blue with gold front bumper which was replaced after an accident. Has leather interior. Mileage is about 165,000. Automatic.

 

Since my last post someone on the other thread says that I don't have to take the rear housing off...

Been a while.

 

I think the houseing stays in place. A common sized seal. Just remove drive shaft IIR.

I put an indicator on the driveshaft back there. I can move it about 0.030. I'm not sure if there might be something more than the seal, so I'm going to let a transmission shop look at it.

A small amount of play is inherent with that type of design so the shaft can move freely. If there were no play the shaft might get stuck and cause binding.

This is something I wouldn't think twice about. A new seal is only a few dollars and might take 45 minutes to install.

A small amount of play is inherent with that type of design so the shaft can move freely. If there were no play the shaft might get stuck and cause binding.

This is something I wouldn't think twice about. A new seal is only a few dollars and might take 45 minutes to install.

 

Boy do I appreciate you telling me that. This thing has gotten too big in my head, and I appreciate someone with some comments to balance me!

Took this car to the transmission shop, and they said that the rear seal was totally blown out. So they put a new one in. I didn't get any info on the play at the back. They didn't like having talking to me too much.