The official notice
Defect
This recall affects certain trucks equipped with optional 18", 20", or 22" wheels and tires. The spare tire has a smaller diameter than the tires on the truck. As a result, the antilock brake system (ABS) may not work properly on certain road surfaces when the spare tire is installed on a rear wheel position. This could lead to an increase in stopping distance or a loss of control.
Safety Risk
Reduced braking or a loss of control could increase the risk of a crash.
Remedy
General Motors will notify owners by mail and advise you to bring your truck to a dealer to replace the spare tire and wheel. The dealer will also apply a new spare tire information label over the existing tire label. You will be provided an owner's manual insert that says which spare tire should be used with the wheels and tires on your truck.