ENGINE OIL DISCOLORATION EXPLANATION OF COLOR

VEHICLES AFFECTED: ALL CARS EQUIPPED WITH 2.0L L4 OR THE 2.8L V6. (ENGINE CODES B, P, X, Z, L, 1) ALL C, G, K, P, S & T MODEL TRUCKS WITH CHEV BUILT ENGINES AND ALL C-5, 6, & 7000 MODEL TRUCKS WITH CHEVROLET BUILT GAS ENGINES. (ENGINE CODES Y, B(2.8L), D F,H,A,K,L,M,P,B(6.0L),C,J,E,S,W) CERTAIN ENGINE ASSEMBLY PLANTS MAKE USE OF AN ENGINE OIL DYE FROM TIME TO TIME IN VARIOUS ENGINES TO AID IN DETECTING ENGINE OIL LEAKS DURING THE ASSEMBLY PROCESS. THE DYE USED CAUSES THE OIL TO GLOW BRIGHT YELLOW WHEN EXPOSED TO A BLACKLIGHT. SOME OF THE DYE MATERIAL USED GIVES THE ENGINE OIL A SLIGHT RED TINT AND IN SOME CASES HAS BEEN MISTAKEN FOR AUTOMATIC TRANSMISSION FLUID...THE DYE IS IN NO WAY HARMFUL TO THE ENGINE, AND THE OIL SHOULD NOT BE CHANGED IF THE ABOVE DESCRIBED CONDITIONS ARE SEEN.

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.