GM Service Manual Online
For 1990-2009 cars only

ENGINE COOLANT LOSS ADDITION OF COOLANT SUPPLEMENT

VEHICLES AFFECTED: Models Equipped with 3.0L (VIN Codes L & E) And 3.8L (VIN Codes A, 3 & 9) V-6 Engines

Whenever a vehicle equipped with one of the above engines is experiencing a possible coolant loss condition, refer to the diagnosis section of Part 6B of the 1985 Chassis Service Manual. In inspecting for leaks particular attention should be given to hose clamps and difficult to inspect areas (i.e. throttle body).

After repairs have been made, three pellets from Engine Coolantt Supplement, Part Number 3634621* (or equivalent such as Bar's Leak), should be added to the coolant.

Additionally, whenever it becomes necessary to open up the cooling system for repair on one of these vehicles, or the coolant is changed for any reason, the coolant supplement should be replenished to return the system to the original factory level protection by again adding three pellets to the coolant.

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.