The method for automatic transmission fluid and filter replacement in a 4l80-e/4l85-e transmission starts by lifting and supporting the vehicle before placing a drain pan under the transmission
Oil Pan to remove the Drain Plug when present until all fluid drains out. The Drain Plug threads must receive a small amount of fluid sealant gm p/n 12346004 or canadian p/n 10953480 before installation and tightening to 18 nm (13 ft. Lbs.). You must support the transmission with a transmission jack before removing the transmission mount nuts and support bolts as well as side bracket bolts and bracket. Remove the transmission range selector cable bracket bolts along with the bracket while maintaining attachment of the selector cable to its bracket. Disconnect the range selector cable end from the transmission range selector lever ball stud. The procedure now requires removing Oil Pan bolts while checking the reusable Oil Pan Gasket followed by Oil Pan and gasket removal. Start by removing the magnet which rests at the bottom of the pan. Then detach the
Oil Filter with filter neck seal while cleaning the transmission case and Oil Pan Gasket surfaces with solvent. The process begins by implementing the filter neck seal and Oil Filter after which you should install the Oil Pan Gasket to the pan before adding the magnet if required. Set the bracket with cable in position before attaching the transmission range selector cable bracket and securing its bolts at 25 nm (18 ft. Lbs.). Next attach the Oil Pan with bolts and tighten them to 24 nm (18 ft. Lbs.). Use the transmission range selector cable end to attach the ball stud of the range selector lever before installing the transmission support along with side bracket and bolts to a torque of 95 nm (70 ft. Lbs.) and finally torquing the transmission mount nuts to 40 nm (30 ft. Lbs.). Take out the transmission jack then reduce the height of the vehicle while adding dexron® iii transmission fluid until reaching the recommended level.