I have a 97 legacy gt. last week when I was going down the interstate, I noticed smoke behind my car and pulled over. When I opened the hood,I noticed oil all over everything at the bottom back of the motor, by the tranny. I got it to the shop and they decreased it and drove it and couldn't find a leak anywhere. It appeared to be gear oil from the tranny and the fluid was a little low. I have drove it several times since and had no problem til the other day. Once again I was on the interstate, but this time for much longer, when once again smoke is pouring out of the back of my car. Same problem,gear oil blown all over and burning off. Have you ever heard of this happening?

Is the oil coming up out of the dipstick tube?

I would normally expect this if it were overfilled. Overfilling causes the fluid to cavitate and foam.

 

Is this a manual or auto trans? How old is the oil?

The mechanic doesn't think it's coming out of the tranny dipstick. It's a manual. I don't know how old the tranny fluid is, I've owned the car for a year and a half.

Should be pretty easy to see if its coming out of the dipstick tube. Look straight down behind the intake box on the engine. Little yellow handle is the trans dipstick. There is an o-ring on the dipstick that can dry out and shrink, then pressure in the trans causes the dipstick to pop out and let oil leak out.

See if the tube or the area around it looks wet. There might be some dirt and crud there but it shouldn't look wet under the tube.

 

If its clean and dry by the dipstick tube then the oil is coming from the input shaft seal and that means the mainshaft bearing is bad.

Front input shaft seal on the trans.

 

Happens more at high speed, because the ring gear slings oil right at the back of the seal, the faster you go, the more oil hits it.  In my experience, speeds over 75-80 will make it happen for sure.

 

I would replace the input shaft front and rear bearings, and all the seals in the trans while it's open.

 

About $200 worth of parts+ labor

Last week when it happened, I was on the interstate for about 20 minutes doing about 75. This week, I was on the interstate about an hour and a half doing about 75 when it happened. I know the tranny fluid was not over full. There was gear oil everywhere, so it's hard to tell where it's coming from.

Last week when it happened, I was on the interstate for about 20 minutes doing about 75. This week, I was on the interstate about an hour and a half doing about 75 when it happened. I know the tranny fluid was not over full. There was gear oil everywhere, so it's hard to tell where it's coming from.

 

I told you.  It's coming from the front seal of the input shaft.

 

The ring gear slings gear oil DIRECTLY at the back of the seal at high speeds.

 

The transmission needs new input shaft seal, and you should replace the input shaft bearings while you're in there.

Thank you. Does the tranny need to be pulled to replace these bearings and seals?

Yes, trans needs to be pulled out and opened up.

 

here's the write-up I did several years ago. 

 

http://www.ultimatesubaru.org/forum/topic/87305-easy-transmission-front-seal-replacement/

 

 

 

Doesn't cover the Rear Input bearing replacement.....but that's pretty easy......it just presses on....make sure to put the clip towards the rear of the shaft.