1. Raise the vehicle. Support the vehicle with suitable safety stands. Refer to Lifting and Jacking the Vehicle in General Information.



2. Remove the retaining clip bracket nut.
3. For all gas engine, remove the engine oil cooler lines from the retaining bracket.



4. For the 6.5L only, remove the bolt securing the engine oil cooler line from the retaining bracket.



5. For the 4.3L only, remove the engine oil cooler line retaining bolt from the oil filter adaptor .



6. Remove the retaining ring with bent-tip screwdriver or equivalent.



7. Remove the engine oil cooler liner retaining clips in the following manner:

7.1.	Using the bent-tip screwdriver or equivalent, pull on one of the open ends of the retaining ring in order to rotate the retaining ring around the quick connect fitting.

7.2.	Rotate the retaining ring around the quick connect fitting until the retaining ring is out of position and can be completely removed.





Important: When performing following service procedure, do not reuse the old retaining clips. Replace the old retaining clips with new ones.

8. Remove the retaining ring from the quick connect fitting in the following manner:

•	Discard the retaining ring.

•	Pull the engine oil cooler line straight out from the quick connect fitting.




9. For the 5.0L/5.7L only, remove the engine oil cooler lines from the oil filter adaptor, and repeat steps 5 through 7.



10. For the 8.1L only, remove the engine oil cooler lines from the oil filter adaptor, and repeat steps 5 through 7.



11. For the 6.5L only, remove the engine oil cooler lines from the oil filter adaptor and repeat steps 5 through 7.



12. Remove the engine oil cooler lines from the radiator, and repeat steps 5 through 7.



13. Remove the engine oil cooler lines from the auxiliary oil cooler, and repeat steps 5 through 7.

Important: Do not reuse any of the existing retaining rings if the quick connect fittings have been removed. Retaining rings are not reusable. Ensure the following steps are performed when installing the new retaining rings onto the fittings.

1. Do not install the new retaining ring onto the fitting by pushing the retaining ring down over the fitting.



2. Install the retaining ring by hooking the one open end of the retaining ring in one of the slots in the quick connect fitting.



3. Install the retaining ring by rotate the retaining ring around the fitting until the retaining ring is positioned with all 3 ears through the 3 slots on the fitting.



4. Install the retaining clip so that the retaining clip moves freely in the fitting.

Important: After performing the following service procedure, pull back on the engine oil cooler line to ensure the engine oil cooler line is properly seated.

5. Install the engine oil cooler line into the fitting.




Notice: Ensure the cooler line being installed has a plastic cap on each end that connects to a quick connect fitting. If no plastic cap exists, or the plastic cap is damaged, obtain a NEW plastic cap and position the cap on the cooler line prior to cooler line installation.

6. Install the plastic cap onto the fitting.



7. Connect the engine oil cooler lines to the radiator, and repeat steps 1 through 6.



8. Connect the engine oil cooler lines to the auxiliary oil cooler.



9. For the 4.3L only, install the engine oil cooler lines to the oil filter adaptor.



10. For the 5.0L/5.7L only, install the engine oil cooler lines to the oil filter adaptor , and repeat steps 1 through 6.



11. For the 8.1L only, install the engine oil cooler lines to the oil filter adaptor, and repeat steps 1 through 6.



12. For the 6.5L only, install the engine oil cooler lines to the engine.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.




13. For the 4.3L only, install the engine oil cooler line retaining bolt to the oil filter adaptor.

Tighten
Tighten the bolt to 35 N·m (26 lb ft).




14. Install the engine oil cooler line retainers to the frame, except the 6.5L diesel.

Tighten
Tighten the nut to 12 N·m (106 lb in).




15. Install the engine oil cooler lines to the retaining bracket.
16. Install the engine oil cooler line retaining clip to the retaining bracket.
17. Install the retaining clip bolt to the retaining clip.

Tighten
Tighten the bolt 12 N·m (106 lb in).

18. Remove the safety stands.
19. Lower the vehicle.
20. Verify the oil level. Fill the oil as necessary.