Workshop Repair and Service Manuals GMC SIERRA
Articles

Fuel

Gasoline      Use of the recommended fuel is an important part of the proper maintenance of this vehicle. To help keep the engine clean and maintain optimum vehicle performance, we recommend the use of gasoline advertised as TOP TIER...
Fuels in Foreign Countries      Never use leaded gasoline or any other fuel not recommended in the previous text on fuel. Costly repairs caused by use of improper fuel would not be covered by the vehicle warranty. To check the fuel availability, ask an...
California Fuel Requirements      If the vehicle is certified to meet California Emissions Standards, it is designed to operate on fuels that meet California specifications. See the underhood emission control label. If this fuel is not available in states...
Gasoline Specifications (U.S. and Canada Only)      At a minimum, gasoline should meet ASTM specification D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl...
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,...
Fuel E85 (85% Ethanol)      Vehicles that have a FlexFuel badge and a yellow fuel cap can use either unleaded gasoline or ethanol fuel containing up to 85% ethanol (E85). For all other vehicles, use only the unleaded gasoline described under...
Fuel Additives      To provide cleaner air, all gasolines in the United States are now required to contain additives that help prevent engine and fuel system deposits from forming, allowing the emission control system to work properly. In most...
Filling the Tank      If the vehicle has a diesel engine, see the Duramax diesel supplement for more information. WARNING Fuel vapor burns violently and a fuel fire can cause bad injuries. To help avoid injuries to you and others, read and...
Filling a Portable Fuel Container      WARNING Never fill a portable fuel container while it is in the vehicle. Static electricity discharge from the container can ignite the fuel vapor. You can be badly burned and the vehicle damaged if this occurs. To help...