4L80-E/4L85-E Automatic Transmission
Automatic Transmission Fluid/Filter ReplacementRemoval Procedure
1. Raise and support the vehicle.
2. Place a drain pan under the transmission oil pan.
3. Remove all of the oil pan bolts except for the rear bolts.
4. Loosen the rear oil pan bolts approximately 4 turns.
Important: Do not damage the transmission case a the oil pan sealing surfaces.
5. Lightly pry down the front of the oil pan and allow the oil to drain.
6. Remove the remaining oil pan bolts.
7. Remove the oil pan.
8. Remove the gasket.
9. Remove the magnet.
10. Remove the oil filter.
11. Remove the filter neck seal.
12. Transmission oil pan gasket is reusable. Inspect the gasket and replace as needed.
13. Clean the transmission case and the oil pan gasket surfaces with solvent.
14. Air dry the transmission case and surfaces.
Installation Procedure
1. Install the filter neck seal.
2. Install the oil filter.
3. Install the oil pan gasket to the pan.
4. Install the magnet into the bottom of the pan.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan using all seventeen oil pan bolts.
^ Tighten the oil pan bolts to 11 Nm (97 inch lbs.).
6. Install Dexron III Automatic Transmission Fluid. Refer to Fluid Capacity Specifications (Overhaul).
7. Lower the vehicle.
8. Check the oil pan gasket for leaks.