Early mornings for the past three days I go turn the car on. Then I shift the shifter column to "R" and the car doesn't move, then I try shifting to "D,3,2,1" and get nothing. Its feels like the car is in neutral. But as soon as the car warms up I am able to get the car to move in any gear all day long, but as soon as the car sit still for about 8 hours, the problem starts again.
Whats could be the cause of this problem?

I too am having the same problem but I just put it back in park and then try to put it in reverse and it works but I would like to solve the problem before it gets worst.

I know this sounds dumb... but have you checked the transmission fluid?
It sounds like the trans is not getting and fluid flowing through it... if it is not full this could possibly do it. My 99 Lumina is very sensitive even if it is only down a bit.

I can't say for sure, but I would imagine there is a pump like in an oil pan to get the trans fluid to flow. Possibly a problem with the pump?
Someone correct me if there isn't one.

Hope this at least gives you a start.
Hearts88

Yes I added some trans fluid about 3 weeks ago and it went away but it was also warmer weather then too. I live in michigan to explain the temperature change. I had a problem with it two days again when it got colder so I also got the trans fluid flushed out and got a new trans filter. I am not sure if this solved the problem.

The first thing I did was check the oil level and it needed about 1/2 a qt. The problem is still the same.
It could be a transmission pump going bad? or a senior in the transmission? But, I will try changing the filter and oil to see what happens.
For the last few weeks I wake up 5 minutes earlier to let the car warm up and it works fine.

I have heard that the pump noise common in these cars are the transmission pump cavitating, but it is supposedly normal. If you guys were talking about a tried and true old Turbo 350 I would say it is absolutely fluid level or possibly even draining of the torque converter. But I have heard of trouble with the electrical solenoid body on these front drive 4T60E E is for electronic i suppose.

BTW, I have a 94 Old Cutlass supreme convertible with the illustrious(joke) 3.4 dohc