Engine Coolant - Revised Requirements, Recommendations

Bulletin No. I 83-42
File In Group 6A
Number 32
Date Mar. '83
ENGINE COOLANT USAGE - 1982 AND 1983 VEHICLES


Engine coolant-requirements and recommendations have changed due to the increased use of aluminum components on engines used in 1982 and 1983 vehicles. Aluminum engines such as the Cadillac HT4100 require a different formulation of antifreeze to prevent corrosion.

It is required that any additions of coolant to these vehicles be done with GM 1825-M. The antifreeze meeting Cadillac requirements is available from GMWDD in gallons (P/N 1052753) and drums (P/N 1052754).

This new coolant may be added to systems which contain antifreeze meeting previous specifications (GM 1899-M) 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 of coolant which meets aluminum requirements rather than mixing old antifreeze with new as there may be slight differences in their chemical properties that could affect their overall performance.

Procedures for mixing antifreeze to water to obtain the required protection level are unchanged.