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Hey guys
I’ve had my car about a year and it’s been sitting in storage since October. I took it out today for the first time and discovered a trail of transmission fluid from backing it out of the garage. Seems to be coming from the rear of the car, Is this a known problem and what needs to be sealed?
We will need a bit more information to point you in a solid direction. You mentioned transmission fluid, versus diff fluid, so that's a start. Is it auto or manual? Knowing where the fluid is gathering on the transmission will help pinpoint where the leak is propagating from. "Typical" places the C5 manual transmissions leak from would be output shaft seal and/or the square cover on top of the transmission. I can't speak to auto transmissions typical leak points.
If it's either of those locations, you'll most likely need to drop the rear trans axle to properly repair the leak.
Last edited by wscott62893; Mar 29, 2019 at 09:00 AM.
Another common place for a manual trans leak is between the extension housing and the main transmission housing. There's no gasket. Instead, GM used an anaerobic sealant to mate the two surfaces. This sealant breaks down over the years and causes a leak. You will see transmission fluid accumulating around this area when under the car. I took this pic before pulling the drivetrain, replacing the clutch and resealing these surfaces.
How much fluid leaked out? A little fluid can look like a lot. If it is an auto trans, I can offer some advise, if not - I got nuttin.
My '03 auto trans leaked small amounts of tranny fluid occassionally whenever I started the car on cold Colorado days and put it into reverse right away without letting the car warm up. I jacked the car up and looked for the leak and it appeared to be possibly coming from the bottom of the vent tube hose at the rear of the transmission. I cleaned up the underside with brake cleaner and called it good. A few weeks later, I happened again and looked like it spit all over my ps exhaust pipe.
I took my car to a well-respected transmission shop because it was due for the 50k gasket/filter/fluid change anyway. I showed them pics of the fluid on my garage floor (that appeared like a lot of fluid to me) and they said that was a very minimal amount of fluid that I should not be concerned with. The shop owner and techs all thought that the random fluid leaks were coming from the vent hose.
Hasn't happened ever since (knock on wood 3x), however, now I always let the tranny get up in temp. before putting it into reverse on a cold day.
How much fluid leaked out? A little fluid can look like a lot. If it is an auto trans, I can offer some advise, if not - I got nuttin.
My '03 auto trans leaked small amounts of tranny fluid occassionally whenever I started the car on cold Colorado days and put it into reverse right away without letting the car warm up. I jacked the car up and looked for the leak and it appeared to be possibly coming from the bottom of the vent tube hose at the rear of the transmission. I cleaned up the underside with brake cleaner and called it good. A few weeks later, I happened again and looked like it spit all over my ps exhaust pipe.
I took my car to a well-respected transmission shop because it was due for the 50k gasket/filter/fluid change anyway. I showed them pics of the fluid on my garage floor (that appeared like a lot of fluid to me) and they said that was a very minimal amount of fluid that I should not be concerned with. The shop owner and techs all thought that the random fluid leaks were coming from the vent hose.
Hasn't happened ever since (knock on wood 3x), however, now I always let the tranny get up in temp. before putting it into reverse on a cold day.
it is an automatic
a little bit of trans fluid drips out on cold start when car is in reverse
rear of the car near the diff
Another common place for a manual trans leak is between the extension housing and the main transmission housing. There's no gasket. Instead, GM used an anaerobic sealant to mate the two surfaces. This sealant breaks down over the years and causes a leak. You will see transmission fluid accumulating around this area when under the car. I took this pic before pulling the drivetrain, replacing the clutch and resealing these surfaces.
Hey guys
I’ve had my car about a year and it’s been sitting in storage since October. I took it out today for the first time and discovered a trail of transmission fluid from backing it out of the garage. Seems to be coming from the rear of the car, Is this a known problem and what needs to be sealed?
Did you fix this ? Where was the leak from? Mine is doing that.
Rear Trans leak
