See also:

How to Inspect the Engine Air Cleaner/Filter
To inspect the air cleaner/filter, remove the filter from the vehicle and lightly shake the filter to release loose dust and dirt. If the filter remains covered with dirt, a new filter is required ...

Customer Assistance Offices (U.S. and Canada)
GMC encourages customers to call the toll-free number for assistance. However, if a customer wishes to write or e-mail GMC, the letter should be addressed to: United States GMC Customer Assistance ...

Instantaneous Economy and Active Fuel Management™ Indicator
If the vehicle has this display, press the trip/fuel button until INST ECON V8 displays. This display shows the current fuel economy at a particular moment and will change frequently as driving condit ...