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Automatic transmission shift problem.


Josh s.:
Hay fellas. Well heres my problem. Im a young guy bought my first classic its 72 grande but has a 429 thunderjet in it, witch i have to assume wasnt origional.

Anyways short story engine was in ruff shape when perchased the car and soon after broke down on me, big mess.
I sent the car to a mechanic in the city for an engine rebuild and the engine seems great now but. I only just got it back yesterday and it was a long drive back and ive been noticing it has a hard time shifting in all gears.

Its seems i realy gotta put my foot down to get it to shift and then let off because im going to fast if i dont do it im driving around at a realy hight rev. first to second isnt so bad, but 2nd to 3rd is just awful. I realy have to rev it up to get it to go, and again back off the throttle because im going to fast it will stay in when i let it off so i can cruse at propor speeds but to get that i have to punch it every time for it to go to the next gear. 

it realy conserns me because it never had that problem in the short time i got to drive it before the engine went.

I checked the fluid levels they seem just fine and it dosent seem dirty or anything. And unfortunatly i cant tell you what rpm its shifting at because the mechanic i took it to was a real fail at wiring or what ever he did it seems and my rpm guage no longer works.

Like i said im a young guy and im realy new to the game. I could use a hand to figure out whats up with my transmition and how big of a problem im looking at.

Welcome to the hobby!  Nice car you have there.  I think you'll get lots of enjoyment out of it.

There is a vacuum line that goes from the engine to the transmission.  Make sure it's connected at both ends and that it's not leaking.

I had a similar problem in my 65 convertible and it was the vacuum line, only it was hooked up to the wrong vacuum port ( it should be hooked up to manifold vacuum ).

Josh s.:
hay thanks fellas i think that may have done it. its still shiffting a bit late but i think theres some paint in the vacume port from the rebuild. it wasnt connected like you said it had a cap on it. exept looks like it was painted before the cap was put on. 

Once i clean out the port im sure it will shift even better. thanks again guys.


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