th400 shifting rapidly in 3rd
Thread Starter
Teching In
Joined: Apr 2006
Posts: 4
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th400 shifting rapidly in 3rd I rebuild my Jeep CJ7 from scratch and overhaul the engine. I saw a big difference in the compression. I did not measure it but my battery barely start the engine. it's a good news... and a bad one cause i have to change the battery for a dry one.
since then, the tranny goes from one to 3rd very rapidly, under 30 mph. I suspect there is too much vacume..
Is it the case?
Dan
since then, the tranny goes from one to 3rd very rapidly, under 30 mph. I suspect there is too much vacume..
Is it the case?
Dan
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Joined: Apr 2004
Posts: 377
Likes: 0
What transmission are you running? If it has a vacuum modulator, turn in the screw on the modulator a full turn and see what happens? If this improves it, you can turn it in a little at a time, until you get the shifts where you want at part throttle. Do not turn in the screw more than 4 turns total, as this can possibly ruin the vacuum modulator.
No modulator? you either don't have a th400 or have one with the modulator plugged. BUT if it had a modulator plug it would shift late and hard UNLESS someone set it up like this and put some weak governor springs in it with heavy weights.
All very unlikely.
I'd say you don't have a th400.
All very unlikely.
I'd say you don't have a th400.
