Help with leaky 700r4 tranny
Thread Starter
Instructor
Joined: Jun 2004
Posts: 182
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From: Sun Peaks British Columbia
Help with leaky 700r4 tranny
HELP! Could some of you guys with automatic transmissions please check your tranny fluid levels, (cold and engine off) and let me know if your transmission fluid registers well over full please.
Mine does, and I don't know if this is a normal condition. The transmission leaks from the round plate behind the torque converter, and i don't know if it's due to a backflow overflow problem, or just a leaky seal. The transmission is brand new, and I just installed it. I don't cherish the idea of having to take it out again to replace a gasket or an 'O' ring.
A guy at a transmission shop told me that if I have a slight air leak in my radiator cooling tank, that will allow the tranny fluid to syphon back into the transmission. Possible I guess?
Thanks for the help.
Mine does, and I don't know if this is a normal condition. The transmission leaks from the round plate behind the torque converter, and i don't know if it's due to a backflow overflow problem, or just a leaky seal. The transmission is brand new, and I just installed it. I don't cherish the idea of having to take it out again to replace a gasket or an 'O' ring.
A guy at a transmission shop told me that if I have a slight air leak in my radiator cooling tank, that will allow the tranny fluid to syphon back into the transmission. Possible I guess?
Thanks for the help.
Thread Starter
Instructor
Joined: Jun 2004
Posts: 182
Likes: 0
From: Sun Peaks British Columbia
Yup. Mine too goes about a quart above the full mark. I thought this wasn't supposed to happen, but... if everyones does it, it must be normal. Funny, but I always only checked it hot, running, and in park.
Race Director
Joined: Feb 2006
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From: Inside the woods living my passion
St. Jude Donor '07-'08
Originally Posted by yellovette
Yup. Mine too goes about a quart above the full mark. I thought this wasn't supposed to happen, but... if everyones does it, it must be normal. Funny, but I always only checked it hot, running, and in park.
Dont worry what the level is at cold and the engine shut off .. Like yellovette said "checked it hot, running, and in park." Thats how its suposed to be checked.
Burning Brakes
Joined: Jan 2006
Posts: 1,154
Likes: 1
From: St Augustine FL
Originally Posted by C3Racing
Dont worry what the level is at cold and the engine shut off .. Like yellovette said "checked it hot, running, and in park." Thats how its suposed to be checked.
If you check it cold it will show way over full. All of the fluid drains out of the torque converter back in to the pan. Check it hot with the car running in park. It seems I have seen several threads about leaking trannys this week including my own thread.
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Thread Starter
Instructor
Joined: Jun 2004
Posts: 182
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From: Sun Peaks British Columbia
Thanks for the responses guys. I contacted the folks who sold me the tranny and they said there's a gasket around the oil pump and each of the bolts has an 'O' ring as well.
The tranny was just freshly built to my specs, so it seems unlikely that a new gasket or 'O' ring would leak. I mean I've got 0 miles on this thing.
The likely answer is that the oil pump has a hairline fracture at the mounting plate. This might not even be visible when the pump is off, but when you tighten the mounting bolts.... there it is.
They're going to supply me with a new pump and all the gaskets, but what a drag, I'll have to re & re the tranny again. This'll be no.3 attempt.
Third time lucky????
The tranny was just freshly built to my specs, so it seems unlikely that a new gasket or 'O' ring would leak. I mean I've got 0 miles on this thing.
The likely answer is that the oil pump has a hairline fracture at the mounting plate. This might not even be visible when the pump is off, but when you tighten the mounting bolts.... there it is.
They're going to supply me with a new pump and all the gaskets, but what a drag, I'll have to re & re the tranny again. This'll be no.3 attempt.
Third time lucky????
Safety Car
Joined: Jun 2002
Posts: 4,135
Likes: 1
my 700 r-4 had a leak, it was coming from the speedo cable where it screws to the trans,, it didnt look like it was coming from there to me,,the trans shop said they put a extra o ring and it stopped leaking. yes the fluid will register more if you check it cold not running because they drain down higher than the pan gasket, when you start it the pump suckes the fluid, hot is the proper way to check it while its running in park
