I have a 2005 AT 8....It came with the shitty 16" wheels and I just bought the 18" OEMs. The guy sold me the OEMs with the TPMS on them. My old 16" wheels didn't have TPMS. Would my car make any use of the new TPMS on the 18s?

 

That all depends on what the car originally came with! The TPMS sensors transmit to a receiver and an idiot light on the IP. If you don't have the receiver to begin with, no amount of transmitting from the wheel sensors will help.