i have a 09 tahoe and when i put the rear windows down they shake while i drive as if they are loose. the from shake a little too. is this normal or just my truck???

 

Not normal. Take it in.

 

PS1588,
I have an 2007 LTZ and have the same shakey rear windows. I took it back to the dealer and they said this is normal. I made the service manager open several 07 Tahoe on the lot and each one had the same thing.
If your dealer was able to correct this I would be interested in hearing about it.