TH400 will not shift out of first gear.

[NORTHSTAR]

Hi Guys,
Question on a issue i'm having with my tranny, Car starts up fine reverse down the drivway
put in D position hit the gas will not shift out of first gear.
Car is 1970 GS455 turbo 400 trans, Fluid level checked. I recently replaced lifters and pushrods in the engine so the intake came off, Checked fitting in the back of intake manifold everthing appears connected. No issues before the engine work regarding shifting,
Looking for advice on where to start looking for the problem.

as always thanks

Leo

[Dr. Frankenbuick]

Leo,

Make sure that line is still hooked to the Modulator on the transmission. There should be vacuum at the modulator and no leaks in the line to it. That would make it shift late and at a very high rpm.

[NORTHSTAR]

Thanks Steve, That was the problem Found leak at the intake connection to the line.
Shifting just fine now.

Leo

[bobc455]

Happens to everyone!