Fluid Pan: Service and Repair

REMOVAL PROCEDURE
1. Raise the vehicle and support.
2. Place a drain pan under the transmission bottom pan in order to catch the fluid.

Important: Removing the bottom pan on the HYDRAMATIC 4T80-E only partially drains the transaxle fluid. The side cover and the torque converter hold the remaining fluid. To drain fluid from the side cover, remove the drain plug in the case after bottom pan removal. There is no need to drain the torque converter during most service procedures.

3. Loosen the bottom pan bolts. Drain any fluid in the pan.
4. Remove the bottom pan bolts, the pan, and the seal.
5. Inspect the bottom pan for dents or nicks on the sealing surface. If damaged, replace.
6. For proper sealing, clean and dry the bottom pan and the case sealing surfaces. In order to maintain proper bolt torque, the bolts and tapped holes in the case must be clean and dry.

Important: The bottom pan seal is not reusable. Replace with a new seal after removing the bottom pan for any service.

INSTALLATION PROCEDURE
1. Install the bottom pan, new seal, and bolts. Finger-tighten the bolts.





2. Tighten the pan bolts 3 times to the proper specification, in the sequence shown.

NOTICE: Always use the correct fastener in the correct location. When you replace a fastener, use ONLY the exact part number for that application. The manufacturer will call out those fasteners that require a replacement after removal. The manufacturer will also call out the fasteners that require thread lockers or thread sealant. UNLESS OTHERWISE SPECIFIED, do not use supplemental coatings (paints, greases, or other corrosion inhibitors) on threaded fasteners or fastener joint interfaces. Generally, such coatings adversely affect the fastener tightening sequence and specifications. Following these instructions can help you avoid damage to parts and systems.

- Tighten:
^ 1st Time: Tighten the pan bolts to 3 Nm (27 inch lbs.).
^ 2nd Time: Tighten the pan bolts to 6 Nm (53 inch lbs.).
^ 3rd Time: Tighten the pan bolts to 12 Nm (106 inch lbs.).

3. Lower the vehicle.
4. Add DEXRON-III transmission fluid as required.
5. If there was a complete fluid change, reset the transmission oil life indicator. Refer to ELECTRONIC COMPONENT DESCRIPTION.