In Texas, the Front driver and Passenger can't be darker then 35%. The rear windows can be as dark as you like. I have 20% on my Infiniti and i've never been pulled over, niether has anyone else i know with about 20%.

On my '86 Chevy Truck i had 5% tint, was a $80 dollar fine the first time. the second time i got pulled over, it just so happened to be the same cop. I'm not kidding when i tell you he went back to his car and pulled some kind of blade out and ripped both sides of tint film off (its only 3 windows).