Over the years, General Motors has expended considerable effort in the selection of tires for use on its vehicles. In the early days, tires were evaluated within GM by vehicle development engineers and selected primarily on subjective ride and handling evaluations. The tire manufacturer was responsible for certifying his tire's performance in the other areas such as traction and durability. With this type of tire procurement system, each manufacturer's tire was a design created on criteria judged by that manufacturer to be satisfactory. As General Motors tire testing technology increased, the objective evaluation of our supplier's products indicated variations in other areas of performance among our suppliers.
Variation in tire performance from different sources supplying the same size original equipment tire for a specific usage was only one of several reasons why General Motors Management initiated a GM Tire System Improvement Program. Field surveys were conducted which indicated that customers desired improved original equipment tires in areas of performance, warranty, and service. Further, analyses of aftermarket tire performance characteristics indicated that if replacement tires from various sources, while nominally of the same size and type, were intermixed on a vehicle, there could be a resulting change in the vehicle's handling qualities. For GM owners who choose to purchase “TPC” specification tires, the “TPC” system enables them to avoid variations in their vehicle handling due to tires.
In 1971, a Central Tire Group was established to direct the GM Tire System Improvement Program with headquarters located at General Motors Proving Ground. This group was assigned the tire responsibilities to provide: future planning; liaison with tire companies, GM divisions, and the government; evaluation and development of tires; tire specifications; tire quality assurance: service and tire warranty program coordination. Each of these activities then formulated plans to resolve the particular problems related to their areas of concern.