OIL CONTAMINATED BY GAS OIL CHANGE REQUIREMENTS

MODELS: ALL TRUCKS WITH GASOLINE ENGINES

Some trucks that have repeated engine starts/ stops (such as trucks sent to body builders) may have the engine oil contaminated by gasoline. A small amount of gasoline in the oil will boil off at relatively low temperatures, and it will have no detrimental effect on engine performance. However, severely contaminated oil (one or more quarts of gasoline in the oil) can cause erratic engine operation and/or engine damage.

If erratic engine operation occurs, or if the spark plugs are replaced for fouling, the engine oil level should be checked. If the oil level is found to be more than one quart overfilled, the engine oil should be changed. THE OIL FILTER DOES NOT REQUIRE CHANGE. This recommendation applies to trucks at the dealer or the body builder.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.