Tools Required

J 42841-A  Rear Oil Seal Remover. See Special Tools .

IMPORTANT: Although originally equipped with a lip-style crankshaft rear oil seal, engines built from March 1, 1996 and thru 1999 should now use the cassette-style crankshaft rear oil seal.
IMPORTANT: If the engine is in the vehicle, the crankshaft rear oil seal can be removed/installed after the transmission/transaxle and engine flywheel are removed.
IMPORTANT: Crankshaft rear oil seal removal requires adequate space for removal. Mount the engine on a suitable engine stand which will properly space the engine in order to use the J 42841-A  in order to remove the crankshaft rear oil seal. See Special Tools . If necessary, remove the crankshaft rear oil seal with the engine properly supported on the floor or on a bench.
IMPORTANT: Beginning with the model year 2006 the flywheel/flexplate crankshaft bolt hole thread was changed from 8 x 1.25 mm to 11 x 1.5 mm. The J 42841-A  will service the cassette seals installed on engines from March 1, 1996 and later. See Special Tools . If the older J 42841 is to be used on a 2006 or later engine the update kit, J 42841-10, must be used to convert the J 42841 to a J 42841-A  . See Special Tools .
Fig 1: View Of J 42841 Removing The Rear Crankshaft Oil Seal
Courtesy of GENERAL MOTORS CORP.
1. Install the J 42841-A  plate onto the crankshaft. See Special Tools . The hub on the crankshaft will fit into the recess on the inboard side of the J 42841-A  plate. See Special Tools .
Fig 2: Identifying J 42841 Crankshaft Rear Oil Seal Remover
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Northstar engines 2005 and older have an 8 x 1.25 mm flywheel/flexplate crankshaft bolt hole thread. Northstar engines 2006 and later have an 11 x 1.5 mm flywheel/flexplate crankshaft bolt hole thread.
2. Use the proper bolts from the J 42841-A  to retain the plate in place. See Special Tools . Use the bolts (1) 8 mm or the bolts (2) 11 mm.
Fig 3: Placing Screws into Seal
Courtesy of GENERAL MOTORS CORP.
3. Using a drill motor, variable speed preferred, with a socket adapter, install eight 25 mm (1.0 in) self-drilling screws into the seal using the guide holes in the removal tool. When drilling, ensure the drill motor speed is reduced when the screw begins threading into the seal.
Fig 4: View of J 42841 Retaining Bolts
Courtesy of GENERAL MOTORS CORP.
4. With all eight removal screws installed, remove the J 42841-A  retaining bolts. See Special Tools .
Fig 5: Identifying J 42841 Center Forcing Screw
Courtesy of GENERAL MOTORS CORP.
5. Install the center forcing screw.
Fig 6: Removing J 42841 from Crankshaft
Courtesy of GENERAL MOTORS CORP.
6. Tighten the center screw on the J 42841-A  in order to pull the seal assembly off the end of the crankshaft. See Special Tools .
Fig 7: Identifying Rear Crankshaft Seal Bore & Flange
Courtesy of GENERAL MOTORS CORP.
7. After removing the crankshaft rear oil seal inspect the engine block bore (1) and the crankshaft flange (2) for the damage. Repair or replace any damaged components.