AT transmission started leaking
Instructor
Joined: Jul 2016
Posts: 222
Likes: 11
From: Plymouth MI
Do you have lots of bubbles on your dipstick when you check the trans fluid with the engine warmed up?
I've noticed what looks like transmission fluid foam covering my dipstick and it registers about 1/4 inch above the full/hot hash marks.
That's the problem with an overfull transmission, it turns into a foamy dextron latte. It's also bad for the trans so I was going to do a transmission service soon here and check that the filter hasn't fallen off the valve body.
Did you recently have the transmission serviced, or did anyone at an oil change place top up your fluid? If it's overfull it will pump it out the vent, plus bubbles/foamy trans fluid is bad for lubrication.
I've noticed what looks like transmission fluid foam covering my dipstick and it registers about 1/4 inch above the full/hot hash marks.
That's the problem with an overfull transmission, it turns into a foamy dextron latte. It's also bad for the trans so I was going to do a transmission service soon here and check that the filter hasn't fallen off the valve body.
Did you recently have the transmission serviced, or did anyone at an oil change place top up your fluid? If it's overfull it will pump it out the vent, plus bubbles/foamy trans fluid is bad for lubrication.
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,074
From: Lansing MI
If the trans fluid temp gets to high (usually because the trans is slipping) then fluid will belch out the vent and make a huge mess all over the underside of the car. If your particularly unlucky it will end up on the exhaust and catch fire, so you suold probably get it fixed before you drive it much more.
Instructor
Joined: Jul 2016
Posts: 222
Likes: 11
From: Plymouth MI
Could be a tail shaft seal, or front transmission seal. You'll have to clean all that oil up and then see where it's coming from, or you could pay someone else to do it.
You could also have a bad pan gasket, or a leaking dipstick tube housing, or a leaking trans cooler line. Any good mechanic should be able to spot it.
You could also have a bad pan gasket, or a leaking dipstick tube housing, or a leaking trans cooler line. Any good mechanic should be able to spot it.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
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Thread Starter
Drifting
Joined: Apr 2014
Posts: 1,396
Likes: 129
From: Plainfield IN
I didn't add fluid until after I discovered I had a leak - after I added a +quart the level went up to just above the add line. I've only had this car 3 weeks and didn't check the fluids because the dealer had serviced the car.
Intermediate
Joined: Jun 2013
Posts: 27
Likes: 0
Had a very similar problem with my trans. Called the vendor and he nailed it, the TV grommet was split/torn. If it needs to be replaced clean the port install the new grommet with a soap solution also soap the TV when inserting it in the grommet. Hope this helps you.
Instructor
Joined: Feb 2015
Posts: 234
Likes: 20
From: Stuart Florida
Thread Starter
Drifting
Joined: Apr 2014
Posts: 1,396
Likes: 129
From: Plainfield IN
I have a 1994. This past winter I was leaking from tail extension seal and speedo sending unit. I also replaced the front seal. If you have it done, make sure they do the speedo seal, too. I had never dropped an AT before, but it isn't that difficult a DIY, and you could save $1190.00 of that $1200 bill...Just sayin'
Melting Slicks
Joined: Nov 2013
Posts: 3,451
Likes: 336
From: Greater Cincinnati Area.
Just a note to others who may find this in the future.
It is not uncommon at all for a transmission to leak after being parked for several hours, but not leak otherwise. Even when running on a lift.
What happens is the torque converter drains back to sump after a while, past the pump bushing and the pan is then a little overfull.
If you don't realize this it can be maddening to lay under the thing with it running and not see a leak anywhere.
It is not uncommon at all for a transmission to leak after being parked for several hours, but not leak otherwise. Even when running on a lift.
What happens is the torque converter drains back to sump after a while, past the pump bushing and the pan is then a little overfull.
If you don't realize this it can be maddening to lay under the thing with it running and not see a leak anywhere.