Removal Procedure

Remove the fuel tank. Refer to Fuel Tank Replacement .
Disconnect the evaporative emission (EVAP) lines from the sender. Refer to Quick Connect Fitting(s) Service (Plastic Collar) .
Disconnect the fuel line from the sender. Refer to Quick Connect Fitting(s) Service (Metal Collar) .
Reposition the fuel feed and EVAP lines in order to access the lock ring.

Fig 1: Identifying Lock Ring
Courtesy of GENERAL MOTORS CORP.

NOTE: Avoid damaging the lock ring. Use only J-45722 to prevent damage to the lock ring.

NOTE: Do Not handle the fuel sender assembly by the fuel pipes. The amount of leverage generated by handling the fuel pipes could damage the joints.

IMPORTANT: Do NOT use impact tools. Significant force will be required to release the lock ring. The use of a hammer and screwdriver is not recommended. Secure the fuel tank in order to prevent fuel tank rotation.
Use the J 45722 and a long breaker-bar in order to unlock the fuel sender lock ring. Turn the fuel sender lock ring in a counterclockwise direction.

Fig 2: Removing The Fuel Sender From The Fuel Tank

Courtesy of GENERAL MOTORS CORP.

Remove the fuel sender (2) from the fuel tank.
Remove and discard the fuel sender O-ring seal.
Clean and inspect the fuel sender assembly O-ring seal sealing surfaces.

Fig 3: Checking Lock Ring For Flatness
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: Some lock ring were manufactured with DO NOT REUSE stamped into them. These lock rings may be reused if they are not damaged or warped.

IMPORTANT: Inspect the lock ring for damage due to improper removal or installation procedures. If damage is found, install a NEW lock ring.

IMPORTANT: Check the lock ring for flatness.
Place the lock ring on a flat surface. Measure the clearance between to lock ring and the flat surface using a feeler gage at 7 points.
If the warpage is less than 0.41 mm (0.016 in), the lock ring does not require replacement.
If the warpage is greater than 0.41 mm (0.016 in), the lock ring must be replaced.