SERVICE GUILD: 1990 VEH. OIL CLASSIFICATION RECOMMENDATIONS

Starting with the 1990 model year vehicles, Cadillac has upgraded its recommended oil API (American Petroleum Institute) classification. A new category of engine oil performance has been established to provide a higher level of protection and fuel economy for today's modern engines. The new API Service "SG" classification will automatically contain the "CC" performance requirements (for diesel engine applications) and upgrade the "SF" category applicable to gasoline engines. Oil containers will display the new classification as "API Service SG", or it may be displayed as a series: SF/CC, SG or SF/CC, SG/CD. The customer should also look for "Energy Conserving II" for maximum fuel economy.

SG oils have been formulated to provide significant performance improvements over "SF" oils in these areas: valve train wear, oil sludge build up, oil oxidation, and piston deposit formation. Rust and corrosion (including bearing corrosion) and oil consumption protection requirements are unchanged from the SF/CC to SG oils. Overall, these new "SG" oils will provide our customers with cleaner-running, more efficient, and longer-lasting engines.

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.