GM/Detroit 6.5L ENGINE CONTROLS – Fuel Tank Replacement (Suburban)

Removal Procedure
Tools Required
J 36608 Fuel Sender Tool

Caution: Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come In contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cables.
2. Drain the fuel from the tank. Refer to Fuel Tank Draining Procedure.
3. Raise the vehicle.
4. Remove the bolts and the fuel tank off-road shield, if equipped.
5. Loosen the filler neck hose clamp at the fuel tank and disconnect the fuel tank filler neck from the fuel tank.

6. Support the fuel tank and remove the tank strap bolts, the tank straps and the insulator strips, if equipped.

7. Lower the fuel tank and shield enough to access the fuel lines and electrical connections at the tank and sender.
8. Disconnect the fuel feed and vapor hoses.
Disconnect the electrical connections at the sender.
9. Lower the tank and shield fully.
10. Lift the tank out of the shield and place the tank on the floor.

11. Remove the fuel sender assembly and seal ring, using the J 36608 fuel sender tool. Discard the old seal ring. Purge the tank, if the tank is being repaired.

Installation Procedure
1. Install the new seal ring and reinstall the sender using the J 36608 fuel sender tool.
2. Place the tank in the shield.
3. Raise the tank slightly and reconnect the fuel feed and vapor hoses and the electrical connections at the sender.

4. Raise the tank and shield fully.

5. Reinstall the fuel tank filler neck to the tank.
Notice: Refer to Fastener Notice in Cautions and Notices.
6. Install the clamp
Tighten
Tighten the clamp to 2.5 N-m (25 lb in).

Notice: Refer to Fuel Tank Strap Nuts Notice in Cautions and Notices.
7. Install the fuel tank brackets with insulator strips in place.
Tighten
Tighten the strap bolts to 45 N-m (33 lb ft).

8. Install the fuel tank off-road shield, if equipped.
9. Install the bolts.
Tighten
Tighten the bolts to 35 N-m (26 lb ft).
10. Replenish the fuel in the tank. Reinstall the fuel tank filler cap.
11. Reconnect the negative battery cable. If a memory retention device was not used, please reset (to the extent possible) all devices that lost their memory after the battery was disconnected.
12. Check for leaks.
12.1. Turn ON the ignition switch for 2 seconds.
12.2. Turn OFF the ignition switch for 10 seconds.
12.3. Again, turn the ignition switch to the ON position.
12.4. Check for fuel leaks.