Long old thread...quite informative...So, did I get this straight? For the 05 Xfires, they used one of 2 different TPMSensors? If this is so, would it be true that you wouldn't know which one you had until you break down the tire? I just got quoted 100 bucks a tire including rebalancing and mounting and programming the sensor each. Having 2 - '05's this is looking like an $800.00 investment that was unseen, unpredicted.