TH400 leaking from filler tube & shift shaft
09-23-2007, 07:50 AM
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TH400 leaking from filler tube & shift shaft It seems to leak under pressure during hard driving such as a trip down the 1/4 mile. Looks like it's coming out from the fill tube at the trans & on the other side where the gaer selector shaft goes in the side of the trans. The fill tube is an aftermarket flexible unit that appears to just snap in to the trans & is held by the friction of the o-ring on it. I pulled it out & oil started oozing from the hole. I assume there is a vent somewhere on the trans. It has a cast aluminum pan that's maybe an inch deeper that the GM pan. When I drained the fluid for an oil change I got about 6 1/2 qts out.
Should it have the kind of pressure inside that would blow oil out under heavy load?
Could the filler tube/dipstick be out of calibration & the trans is over full?
Where's the vent & how can I check it for proper function?
Thanks in advance.
Should it have the kind of pressure inside that would blow oil out under heavy load?
Could the filler tube/dipstick be out of calibration & the trans is over full?
Where's the vent & how can I check it for proper function?
Thanks in advance.
09-23-2007, 01:46 PM
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I recently pulled my TH400 and when i pulled the filler tube, I also had fluid gushing out, so I think it's normal. I use the madman filler tube/dipstick and have no leaks. Clean off the face of the vent then use compressed air to make sure it's not clogged. Maybe pull the vent off and inspect it.
Dan
Dan
09-23-2007, 02:20 PM
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I think I found the vent tube. It's a short plastic tube maybe 1/8 diameter, comes from the top of trans, can't get the mity vac to work on it since it isn't stiff enough to seat a tapered end adaptor into it so I'll try compressed air. Has anyone changed the seal on the gear selector shaft where it goes in the side of the trans? Can I do that with out dropping the trans?
09-23-2007, 07:45 PM
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I just looked at my vent tube. it's a white piece of plastic with a green cap on the end that sticks out about 1 inch on top of the trans. It's also about 5/16-3/8" in diameter, way bigger than your 1/8" diameter, just FYI.
Dan
Dan
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09-24-2007, 10:17 AM
#8
oil level when ever your car sets for a while the converter will slowly drain back into the trans. remember 1/2 the tc is above center. leaks may appear when not there with the engine running. that is way you check oil levelwith the engine running
