ENGINE COOLANT USAGE ANTI-FREEZE SPECS CHANGE

Chevrolet Motor Division has in past model years recommended use of ethylene glycol base anti-freeze that meets GM Specification 1899-M. This recommendation has changed for 1982 and 1983 vehicles which are factory filled with coolant which meets GM 1825-M specifications. It is required that any additions of coolant to these vehicles be done with GM 1825-M. This change was necessary due to the use of aluminum components on some engines which required a different formulation of anti-freeze to prevent corrosion. This anti-freeze is available from WDDGM in gallons and drums as P/N 1052753 and P/N 1052754.

This new coolant may be added to systems which contain anti-freeze meeting the GM 1899-M specifications with no adverse effect, but it is recommended that when a complete draining of a cooling system is performed such as for engine repair, that it be refilled with one source rather than mixing old anti-freeze with new as there may be slight differences in their chemical properties that could affect their overall performance.

Procedures for mixing anti-freeze to water to obtain the required protection level are unchanged.

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.