did all 07 classic silverados come with TPMS? where are the sensors located?
if theyre in the wheels how does that work?

 

everything 08 and up WILL BE REQUIRED to have TPMS. The 07s should and GM's is the black valve with a star nut that holds the actual sensor to the black valve. Kinda pain in the *** but kinda nice as well. Easier than having to rebuild the metal sensors every time.