Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the vehicle is equipped with the Tire Pressure Monitoring System. If a diagnostics check is needed between e-mails, push 
, and an Advisor can run a check.
See also:
Wheel Alignment and Tire Balance
The tires and wheels were aligned and balanced at the factory to provide the
longest tire life and best overall performance. Adjustments to wheel alignment and
tire balancing will not be necessary ...
Tips and Troubleshooting Chart
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Wheel Alignment
Wheel alignment is critical for ensuring that the tires deliver optimal wear and performance.
• Signs that the alignment may need to be adjusted include pulling, improper vehicle handling, or unusu ...