TH 400 issue
Thread Starter
Instructor
Joined: Jan 2021
Posts: 134
Likes: 22
From: Houston, Texas
UPDATED: TH 400 issue
Hello All,
My 75 ran and shifted great until it developed a fuel leak at the carburetor.
After having the carburetor rebuilt, now my transmission doesn't want to shift out of 1st. Fluid level is fine and the only change was the carb being rebuilt.
Any ideas where to start looking? All help appreciated.
My 75 ran and shifted great until it developed a fuel leak at the carburetor.
After having the carburetor rebuilt, now my transmission doesn't want to shift out of 1st. Fluid level is fine and the only change was the carb being rebuilt.
Any ideas where to start looking? All help appreciated.
Last edited by Steve Stroman; Sep 12, 2022 at 08:35 PM. Reason: Update
Thread Starter
Instructor
Joined: Jan 2021
Posts: 134
Likes: 22
From: Houston, Texas
OK, I checked both ends and they seem fine, but I replaced the hoses anyway.
Shifts great until it warms up (car never gets above 195*) and then it won't shift again. Should I consider a new vacuum modulator?
Shifts great until it warms up (car never gets above 195*) and then it won't shift again. Should I consider a new vacuum modulator?
Melting Slicks
Joined: Sep 2006
Posts: 2,815
Likes: 470
From: Wichita Kansas
Mine never completely stopped shifting but there were times after it was warmed up that it only really just eased from 2nd to 3rd. I replaced my modulator and the problem went away. '72 TH400....
Thread Starter
Instructor
Joined: Jan 2021
Posts: 134
Likes: 22
From: Houston, Texas
UPDATED TH 400 issue
I put in a new modulator and thought it was all good. Drove for about 45 minutes with no problem, shifting OK.
Later I went for a drive and got on it some, now no more shifting again.
Any other ideas?
Later I went for a drive and got on it some, now no more shifting again.
Any other ideas?
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