Author Topic: Fighting this for 2 yrs. leaking shifting fork on 400 turbo help  (Read 150 times)

Offline Mr.Pontiac

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Replaced twice with a Napa unit still after running car at the drags all day, next morning a trial of fluid  a foot long same place. Any ideas??? Yes replaced seals also. very anoying to say the least. stream coming out from under car. Jacking up car again today. Maybe ill try some epoxy around the area??/? Help!!! Tired of cleaning up the mess.

Offline tayto

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Re: Fighting this for 2 yrs. leaking shifting fork on 400 turbo help
« Reply #1 on: August 29, 2019, 09:23:59 AM »
Did you remove shifter shaft and see what shape its in where the seal rides? Have you verified that the full mark is at the pan flange (transmission side) + gasket thickness. Have fixed a few leaking TH400s because the aftermarket dip sticks were well above the pan rail.

Offline Cliff Ruggles

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Re: Fighting this for 2 yrs. leaking shifting fork on 400 turbo help
« Reply #2 on: September 04, 2019, 04:16:27 AM »
You should be using a fill tube with the multiple lip seal, they never leak.

If it's actually leaking at the manual shaft seal as mentioned remove the shaft and check it for scoring/damage.  Replace it if/as needed.  Make sure the case isn't "gouged" where the manual shaft seal sits.

Not much more to it than that, pretty easy repair and those aren't problem areas with TH400's.....Cliff

Offline Cliff Ruggles

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Re: Fighting this for 2 yrs. leaking shifting fork on 400 turbo help
« Reply #3 on: September 04, 2019, 04:17:24 AM »
PS:  another place often missed is leaking at the pump, fluid can "migrate" lower and look like it's leaking from the manual shaft seal or pan.....

Offline Mr.Pontiac

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Re: Fighting this for 2 yrs. leaking shifting fork on 400 turbo help
« Reply #4 on: September 12, 2019, 12:08:48 PM »
Draining pan this week again, its leaking a little under shifting bracket that bolts to tranny housing. plus fork. Here i go again. hardest part torquing down bolts 25ft. pounds on you back with car up only 8 to 10 inches. Ill get it/