Recommended Fuel
Use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise, commonly referred to as spark knock, might be heard when driving.
If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service.
See also:
Tire Pressure
Tires need the correct amount of air pressure to operate effectively.
Notice: Neither tire underinflation nor overinflation is good.
Underinflated tires, or tires that do not have enough air, can re ...
New for 2011
The Sierra Hybrid gets GM's OnStar 9.0 telematics system that GM says
provides better voice recognition. GM also said they have worked to cut down on
the amount of wind noise occupants hear. ...
Power Reclining Seatbacks
To adjust a power seatback, if available:
○ Tilt the top of the control rearward to recline.
○ Tilt the top of the control forward to raise. ...