GM/Detroit 6.5L ENGINE CONTROLS – Fuel Tank Replacement (Cab and Chassis Rear Tank)

Removal Procedure
Tools Required
J 36608 Fuel Sender Tool
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 fuel tank off-road shield bolts, if equipped.
5. Remove the fuel tank off-road shield, if equipped.

6. Loosen the filler neck hose clamp at the fuel tank and disconnect the fuel tank filler neck from the fuel tank.

7. Support the fuel tank and remove the tank straps and insulator strips, if equipped.

8. Lower the fuel tank enough to access the fuel lines and electrical connections on the tank and sender.
9. Disconnect the fuel hoses and lines. Disconnect the electrical connections at the sender.
10. Lower the tank fully.

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.
2. Use the J 36608 fuel sender tool in order to reinstall the sender.
3. Raise the tank slightly and reconnect the fuel hoses, the lines, and the electrical connections at the sender.

4. Raise the tank 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).

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

9. Install the fuel tank off-road shield, if equipped.
10. Install the fuel tank off-road shield bolts, if equipped.
Tighten
Tighten the bolts to 11 N-m (100 lb in).
11. Replenish the fuel in the tank.
12. Reinstall the fuel tank filler cap.
13. Reconnect the negative battery cable. If a memory retention device was not used, reset (to the extent possible) all devices that lost their memory after the battery was disconnected.
14. Check for leaks.
14.1. Turn ON the ignition switch for 2 seconds.
14.2. Turn OFF the ignition switch for 10 seconds.
14.3. Again, turn the ignition switch to the ON position.
14.4. Check for fuel leaks.