AUTOMATIC TRANS. COOLER REPL. (INFORMATIONAL)

SUBJECT: INFORMATION ON AUTOMATIC TRANSMISSION COOLER REPLACEMENT

MODELS: 1993 AND PRIOR LIGHT DUTY TRUCKS EQUIPPED WITH AUTOMATIC TRANSMISSIONS

When inspection of an inoperative automatic transmission reveals metal material in the oil pan, the transmission oil cooler (located in the radiator end tank) must be replaced. The cooler lines must also be flushed to prevent any debris from entering the transmission oil cooler or the transmission.

If inspection reveals friction material or fluid contamination (but no metal), the transmission cooler must be flushed and a flow check MUST be performed. It is essential to flush the cooler after SRTA installation, major overhaul, in the case of pump or torque converter replacement, or when fluid contamination is suspected. Use Kent-Moore tool J35944 and solvent J35944-20 to flush the cooler. Follow the instructions published in each Service Manual, Section 7A, On Vehicle Service, Transmission Cooler Flushing.

SERVICE PARTS INFORMATION

Refer to section 4.128 of the appropriate GMSPO parts catalog for transmission oil cooler applications.

WARRANTY INFORMATION

For vehicles repaired under warranty, use:

Labor Op Labor Time -------- ---------- J3080 See applicable Labor Time Guide.

Note: If transmission is to be replaced with SRTA, do not use ADD condition H (To Replace Transmission Oil Cooler - 0. 7 hr). Labor Operation K7000 (Transmission Assembly Replace) already includes 0. 7 hr (for transmission cooler flush).

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.