Transmission won't shift into drive after sitting overnight

[Toadster]

Hello,

The transmission in my Grand Prix will not shift into drive after sitting overnight. It will finally go into drive after the engine has been running for a minute or two. I'm not sure if revving the engine or changing gears makes a difference. The transmission shifts fine while driving and will even shift into drive if the car has only been sitting for a few hours.

I checked the fluid and it was a little low, but filling it did not make a difference. Does anyone have any ideas as to what could be causing the problem? Will it be an easy fix or an expensive rebuild?

TIA,
Brandon

 

[gtpinsc]

will it go in first, second, third manually on cold start?

 

[Toadster]

If I put the stick on 1, 2, 3, R, or D I get the same results.

 

[Toadster]

It also only happens when the car is parked with the front end on the low portion of a slope.