GM Service Manual Online
For 1990-2009 cars only

INFO. ON SERVICING VEHICLE WITH CONTAMINATED TRANS. FLUID

Subject: INFORMATION ON SERVICING VEHICLE WITH CONTAMINATED TRANSMISSION FLUID

Models Affected: 1993 AND PRIOR YEARS ALL MODELS WITH AUTOMATIC TRANSMISSION OR TRANSAXLE

Antifreeze contaminated trans fluid will cause friction material breakdown and seal degradation. The binder in friction material may dissolve causing material to flake off.

NOTE: ATF contaminated with 1.2 percent glycol antifreeze or more may have a milky translucent appearance.

Just changing trans fluid is not acceptable. Friction material and seals that have been exposed to antifreeze, even for a short time, will eventually show damage. The torque converter cannot be completely drained so contamination would still be present when the remaining fluid circulates through the transmission.

If fluid is contaminated with antifreeze:

1. Locate source of leak and repair/replace radiator as needed.

2. Replace transaxle with SRTA -OR- completely overhaul (including ALL internal/external seals and friction material).

3. Replace torque converter. The torque converter may contain friction material that must be replaced.

4. Flush trans cooler as directed in Service Manual.

Trans fluid additives of any kind are not recommended by General Motors. They are not necessary and in many cases may cause damage to the transmission. Additives will void the transmission warranty.

Under no circumstance does General Motors Corporation recommend the regular and continued use of ANY supplementary additives in General Motors Automatic Transmissions.

The only way to "rejuvenate" a transmission fluid that has broken down is to replace it with new transmission fluid!

General Motors Corporation assumes responsibility for the additives selected by it to remedy specific operating problems.

General Motors Corporation cannot, and will not, accept responsibility for the many other additives which are constantly being marketed.

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.