ENGINE OIL RECOMMENDATIONS INFORMATION

The best lubricating oil you can use in diesel engines is SAE 30 SF/CD; however, SAE 30 SF/CC quality is acceptable. These oils combine excellent film strength with the best available additive package to prevent wear and protect against piston ring sticking at higher mileages. DO NOT USE SAE 10W-40 oils in diesel engines because most of them can cause piston ring stickinq and engine damage.

SAE 30 SF/CD and SF/CC oils are generally not suitable when temperatures fall below 32 DEG F because of cold starting considerations. The use of SAE 15W-40 SF/CD or SF/CC at these lower temperatures (and in extremely cold areas SAE 10W-30 SF/CD or-SF/CC) may be necessary. Study the following chart carefully and follow its recommendations. As always, NEVER exceed the recommended oil change intervals since oil quality deteriorate rapidly with mileage, as carbon accumulates in the oil.

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.