Installation Procedure

Insert a NEW transmission fluid cooler pipe seal into the transmission case hole.
Remove the nub (2) from the DT-41239-1A seal installer (1).

Fig 1: Seal Installer And Transmission Case Bore
Courtesy of GENERAL MOTORS COMPANY
Install the DT-41239-1A seal installer (2) along with the nub (4) to the transmission case bore (3).

Fig 2: Seal Installer And Nub
Courtesy of GENERAL MOTORS COMPANY
Thread the bolt (1) to push the nub (4) with the NEW seal into the transmission.
Install the transmission fluid cooler hose to the transmission. Refer to Transmission Fluid Cooler Hose Replacement .
Lower the vehicle.