GM Service Manual Online
For 1990-2009 cars only

RED COLORED ENGINE OIL LEAK DETECTION AID

Models Affected: 1984 Engine Assembly All

Many of the 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".

Generally, the dye material used gives the engine oil a reddish tint when viewed on the dipstick, and may have a greenish cast when viewed in a glass container. In some cases, the dyed oil has been mistaken for automatic transmission fluid or engine coolant.

The dye is in no way harmful to the engine, and the oil should not be changed if the above described conditions are encountered.

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.