Auto won't shift to 3rd
Thread Starter
Racer
Joined: Jan 2006
Posts: 256
Likes: 0
From: Norfolk VA
Auto won't shift to 3rd
My TH-400 trans always shifted a little late into third, you'd have to go heavy on the pedal then let off and it'd shift, or just late. I put in a new engine where the trans sat for over a year then put behind the new stroker. I hadn't run it more than 100 miles, but it was shifting the way it always did when the modulator popped out from me putting the wrong bracket in to hold it. It dumped a lot of fluid and I coasted right in front of my friend's house. I put in a new adjustable modulator, refilled the fluid and now it won't shift into third. I was in second when it happened. It also feels slightly less positive on the transition from park to 1st and reverse. I took it to a trans shop and they said they want to do a rebuild, but they really don't seem like they know what they're talking about so I want another opinion before I drop the trans (again). Perhaps installing a shift kit might help, or if it's a pressure problem I might need to replace the pump... Any suggestions?
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Did the modulator come all the way out? As in hanging on the hose? There's a valve behind it and it could have blown it out and it's lost. It does have a correct way to install it too- the lands are different from one end to the other..
Thread Starter
Racer
Joined: Jan 2006
Posts: 256
Likes: 0
From: Norfolk VA
Thanks TimAT!! The valve was missing so thanks to a generous GMC Vandura I no longer have a powerglide! If you're ever in the Norfolk area, let me know, I owe you a beer
