Tune-Up - Major

Complete major tune-up service for the 6.7L Cummins diesel including oil and filter change, fuel filter replacement, air filter service, coolant system flush, serpentine belt replacement, and full system inspection.

Warnings

Tools required

Parts

• Engine oil filter × 1 — Mopar 68157291AA or equivalent
• Fuel filter/water separator assembly × 1 — Mopar 68197867AA
• Engine air filter × 1 — Use OEM specification
• Cabin air filter × 1 — Use OEM specification
• Serpentine belt × 1 — Use OEM specification
• Oil drain plug crush washer × 1 — Use OEM specification
• Fuel filter drain valve O-ring × 1 — Use OEM specification

Fluids

• Mopar 5W-20 Synthetic Blend — 13 qt
• Mopar OAT Coolant (Purple) — 18 qt

Preparation

1. Ensure engine is warm but not hot for oil drainage
2. Park vehicle on level surface and engage parking brake
3. Raise front of vehicle and support securely on jack stands
4. Remove engine cover by pulling upward on pull tabs
5. Allow engine to cool sufficiently if performing coolant service (at least 1 hour after shutdown)
6. Place wheel chocks behind rear wheels

Procedure

1. 1

   Drain engine oil
   Position drain pan under oil pan. Remove oil drain plug from bottom of oil pan using appropriate socket. Allow oil to drain completely (approximately 10-15 minutes). Inspect drain plug threads and oil pan threads for damage. Install new crush washer on drain plug and reinstall plug.
   Torque spec

   Oil Drain Plug35 Nm (26 lb-ft)
2. 2

   Replace oil filter
   Locate oil filter on driver side of engine block. Use filter wrench to remove old oil filter, turning counterclockwise. Clean filter mounting surface on engine block. Apply thin coat of clean engine oil to gasket of new filter. Install new filter hand-tight, then tighten an additional 3/4 turn.
3. 3

   Service fuel filter/water separator
   Locate fuel filter housing on top of engine near firewall. Place drain pan underneath. Open water drain valve at bottom of filter housing and drain completely. Close drain valve with new O-ring. Remove filter housing cap by turning counterclockwise. Remove old filter element and clean housing interior. Install new filter element and housing cap. Prime fuel system using manual primer pump on filter housing (pump until firm resistance felt, approximately 50-100 strokes).
   ⚠Failure to properly prime fuel system will cause hard starting and potential air lock
4. 4

   Replace engine air filter
   Open air box by releasing clips on both sides of housing. Remove old air filter element. Inspect air box for debris and clean if necessary. Check air intake duct for cracks or damage. Install new air filter element ensuring proper seating. Close air box and secure clips.
   Torque spec

   Air Box Clips5 Nm (4 lb-ft)
5. 5

   Replace cabin air filter
   Open glove box and remove contents. Press inward on both sides of glove box to release stops and lower completely. Remove cabin air filter access door. Slide out old cabin air filter noting airflow direction arrow. Install new filter with airflow arrow pointing toward rear of vehicle. Reinstall access door and reset glove box stops.
6. 6

   Inspect and replace serpentine belt
   Visually inspect serpentine belt for cracks, glazing, or fraying. Check belt tensioner for proper operation and spring tension. If replacement needed, use belt tensioner tool or appropriate socket on tensioner bolt to rotate tensioner clockwise and relieve tension. Remove old belt, noting routing diagram on fan shroud. Install new belt following routing diagram. Verify belt is properly seated in all pulley grooves.
7. 7

   Drain and flush cooling system
   Ensure engine is completely cool. Place large drain pan under radiator. Open radiator drain petcock at bottom of radiator. Remove radiator cap slowly to vent system. Allow coolant to drain completely. Close drain petcock. Fill cooling system with distilled water, run engine to operating temperature with heater on high, drain again. Repeat flush process until drain water runs clear.
   ⚠️Only perform this step when engine is completely cold to avoid severe burns
8. 8

   Refill cooling system
   Close radiator drain petcock securely. Using coolant refill funnel if available, slowly fill cooling system with Mopar OAT Purple coolant (50/50 premix or properly mixed concentrate). Fill radiator to top. Fill coolant overflow reservoir to MAX line. Start engine and allow to reach operating temperature with radiator cap off. Add coolant as level drops during bleeding process. Monitor temperature gauge to ensure proper thermostat operation. Once air is purged and coolant level stabilizes, install radiator cap. Recheck overflow reservoir level and top off to MAX line.
9. 9

   Refill engine oil
   Lower vehicle from jack stands. Using funnel, pour 12 quarts of Mopar 5W-20 Synthetic Blend into oil fill opening. Install oil fill cap. Start engine and allow to run for 30 seconds, then shut off. Wait 5 minutes for oil to drain to pan. Check oil level with dipstick and add remaining oil to bring level to FULL mark (may require additional 0.5-1.0 quart). Verify no leaks at drain plug or oil filter.
10. 10

    Perform system inspections
    Inspect all fluid levels (power steering, brake fluid, washer fluid, transmission). Check all belts and hoses for proper condition and routing. Inspect battery terminals for corrosion and ensure tight connections. Check all lights for proper operation. Inspect tires for wear and proper inflation (refer to door placard). Look for any fluid leaks underneath vehicle. Check exhaust system for damage or leaks.
11. 11

    Reset maintenance indicators
    Turn ignition to ON position without starting engine. Using instrument cluster controls, navigate to vehicle information menu. Select oil life reset option and confirm reset. If equipped with scan tool, clear any non-critical fault codes and review system status. Record mileage and service date for maintenance records.

Reassembly

1. Reinstall engine cover by aligning clips and pressing firmly until seated
2. Verify all drain plugs, caps, and fasteners are properly installed and tightened
3. Ensure air filter housing and fuel filter cap are securely fastened
4. Double-check that no tools or materials are left in engine compartment

Verification

• Start engine and verify no warning lights remain illuminated after startup sequence
• Check for any fluid leaks around oil filter, drain plug, fuel filter, and coolant hoses while engine runs
• Verify engine reaches normal operating temperature (190-210°F) and cooling fans cycle properly
• Test drive vehicle for 10-15 minutes, monitoring engine performance, temperature, and oil pressure
• Recheck all fluid levels after test drive with engine at operating temperature
• Verify no unusual noises, vibrations, or exhaust smoke during operation
• Confirm fuel system priming was successful by smooth engine operation without surging or hesitation

More procedures for this vehicle