GM Service Manual Online
For 1990-2009 cars only

Use unleaded fuel with all gasoline engines for proper emission control system operation. Using unleaded fuel will also decrease spark plug fouling and extend the engine oil life. Leaded fuel can damage the emission control system, and its use can result in loss of the emission warranty coverage.

The fuel must meet ASTM Standard: D4814 (U.S.), CGSB 3.5-M87 (Canada).

Octane Requirements

Minimum Octane Recommended: 87[(R+M)/2] (pump) octane where R= research octane number, and M= motor octane number.

Gasoline with Alcohol

Notice: Do not spill fuel containing any alcohol on the vehicle. Alcohol can cause damage to the paint finish and trim.

Methyl Tertiary-Butyl Ether (MTBE)

Fuel containing Methyl Tertiary-Butyl Ether (MTBE) may be used, providing there is no more than 15 percent MTBE by volume.

Ethanol

Fuel containing ethanol (ethyl) or grain alcohol may be used, providing that there is no more than 10 percent ethanol alcohol by volume.

Methanol

Notice: Do Not use fuel that contains more than 5% methanol. Use of a fuel (gasohol) that contains more than 5% of methanol can corrode metal fuel system components and damage plastic and rubber parts.

Fuel containing methanol (methyl) or wood alcohol may be used, providing that there is no more than 5 percent methanol by volume.