90K Service

Complete 90,000-mile scheduled maintenance service including oil change, filter replacements, fluid inspections and changes, and full vehicle inspection for the 2007 Ram 3500 with 5.9L Cummins diesel engine.

Warnings

Tools required

Parts

• Engine oil filter × 1 — Use OEM specification
• Fuel filter/water separator assembly × 1 — Use OEM specification
• Air filter element × 1 — Use OEM specification
• Cabin air filter (if equipped) × 1 — Use OEM specification
• Crankcase breather filter × 1 — Use OEM specification
• Drive belt (inspect and replace if worn) × 1 — Serpentine belt - Use OEM specification

Fluids

• 15W-40 diesel engine oil or 5W-40 synthetic — 12 qt
• 75W-90 synthetic gear oil (front differential) — 3.5 qt
• 75W-90 synthetic gear oil (rear differential) — 5.5 qt
• ATF+4 (transfer case) — 2.5 qt
• DOT 3 brake fluid — 1 qt

Preparation

1. Review vehicle maintenance history to determine if transmission fluid, coolant, or brake fluid require replacement based on age or condition
2. Park vehicle on level surface and apply parking brake
3. Place wheel chocks behind rear wheels
4. Allow engine and drivetrain to cool to safe working temperature
5. Gather all fluids, filters, and tools before beginning
6. Verify fluid specifications match vehicle requirements

Procedure

1. 1

   Raise and support vehicle
   Raise vehicle using floor jack at front and rear lift points. Support on jack stands at frame rails. Ensure vehicle is stable and level before working underneath. Remove skid plate if equipped to access oil pan and filter.
2. 2

   Drain engine oil
   Position drain pan under oil pan drain plug. Remove drain plug and allow oil to drain completely (approximately 15-20 minutes for diesel engine). Inspect drain plug washer and replace if damaged. Clean drain plug threads and reinstall drain plug, then tighten to OEM specification (approximately 37 ft-lbs for the 5.9L Cummins oil pan drain plug).
   ⚠Oil may be hot. Wear appropriate gloves and allow time to cool if necessary.
3. 3

   Replace oil filter and crankcase breather
   Locate oil filter on driver's side of engine block. Use oil filter wrench to remove old filter. Clean filter mounting surface and apply thin film of clean oil to new filter gasket. Install new oil filter hand-tight, then tighten an additional 3/4 turn. Replace crankcase ventilation (CCV) breather filter per OEM specification; verify filter location and service interval for this specific engine before replacement.
4. 4

   Replace fuel filter/water separator
   Locate fuel filter assembly on driver's side frame rail. Place drain pan underneath. Open water drain valve at bottom of filter housing and drain completely. Close drain valve. Remove filter housing cap and lift out old filter element. Clean housing, install new filter element with sealing surfaces properly aligned. Prime fuel system using hand primer pump on filter housing until firm resistance is felt and the pump becomes hard to depress, indicating the system is filled. Reinstall housing cap and tighten securely.
   ⚠️Relieve fuel pressure before opening filter housing. Diesel fuel is flammable - keep away from ignition sources.
5. 5

   Service front differential
   Locate fill plug on front of differential housing (upper position) and drain plug on bottom. Remove fill plug first to ensure it's not seized. Remove drain plug and drain fluid into pan. Clean magnetic drain plug of metal particles. Reinstall drain plug and tighten securely. Use fluid transfer pump to add 75W-90 synthetic gear oil through fill hole until fluid reaches bottom of fill hole threads (approximately 2.5-3 quarts — verify capacity against OEM specification). Reinstall fill plug and tighten.
6. 6

   Service rear differential
   Locate the fill plug on the rear differential cover. Note that the AAM 11.5" axle may not have a bottom drain plug — if no drain plug is present, remove the differential cover to drain fluid and replace the cover gasket/sealant on reassembly. Remove fill plug first. Remove drain plug and drain fluid completely. Clean magnetic drain plug of metal particles. Reinstall drain plug and tighten securely. Use transfer pump to add 75W-140 synthetic gear oil through fill hole until fluid reaches bottom of fill hole threads (approximately 4 quarts — verify capacity and viscosity against OEM specification; the AAM 11.5" axle typically requires 75W-140). Reinstall fill plug and tighten.
7. 7

   Service transfer case
   Locate fill plug on rear of transfer case housing and drain plug on bottom. Remove fill plug first. Remove drain plug and drain fluid completely. Clean drain plug and reinstall, tightening securely. Refer to OEM specification for correct transfer case fluid type and capacity (verify ATF+4 vs. dedicated transfer case fluid); typical fill is approximately 2 quarts. Add fluid through fill hole until fluid reaches bottom of fill hole. Reinstall fill plug and tighten.
8. 8

   Replace air filters
   Open engine air filter housing on passenger side of engine bay. Remove old air filter element and clean housing with compressed air or damp cloth. Install new air filter element ensuring proper seating. Secure housing cover. If equipped, replace cabin air filter located behind glove box by removing glove box stops and accessing filter housing.
9. 9

   Inspect and lubricate chassis
   Inspect all grease fittings on suspension, steering linkage, driveshafts, and u-joints. Use grease gun to lubricate all fittings until clean grease purges from joints. Typical locations include: upper and lower ball joints, tie rod ends, drag link ends, track bar ends, driveshaft u-joints, and slip yokes. Inspect all CV boots and u-joint boots for tears or damage.
10. 10

    Inspect drive belt and cooling system
    Visually inspect serpentine drive belt for cracks, glazing, or fraying. Check belt tension and replace if worn beyond limits. Inspect all coolant hoses for cracks, bulges, or soft spots. Check coolant level in overflow reservoir and test coolant freeze protection with hydrometer (should be -34°F minimum). Inspect radiator and intercooler for damage or debris.
11. 11

    Inspect brake system
    Remove all four wheels. Inspect brake pads and rotors for wear, measuring pad thickness (minimum 3mm). Check rotors for scoring or warping. Inspect brake lines and hoses for damage, cracking, or leaks. Check brake fluid level in master cylinder reservoir and inspect fluid condition (should be clear, not dark). Test brake fluid moisture content if possible.
12. 12

    Fill engine with oil and verify fluids
    Add engine oil (15W-40 conventional or 5W-40 synthetic per OEM spec) through oil fill cap; the 5.9L Cummins ISB capacity is approximately 12 quarts with filter change — verify exact capacity against OEM specification and confirm level on dipstick. Install oil fill cap. Check power steering fluid level (ATF+4) and top off if needed. Verify transmission fluid level is within normal range on dipstick when warm. Check windshield washer fluid and fill to appropriate level.
13. 13

    Lower vehicle and start engine
    Reinstall skid plate if equipped. Reinstall all wheels and torque lug nuts in a star pattern to OEM specification (approximately 145 ft-lbs — verify for single vs. dual rear wheel configuration). Lower vehicle to ground. Start engine and allow to idle while checking for leaks at oil filter, drain plug, and all differential/transfer case fill and drain plugs. Monitor oil pressure gauge for normal reading. Allow engine to reach operating temperature.
14. 14

    Final inspection and tire service
    Shut off engine and recheck oil level on dipstick - should be between add and full marks. Check all fluid levels again. Inspect underneath vehicle for any fluid leaks. Check tire pressures and adjust to specification on door jamb sticker. Inspect tire tread depth and wear patterns. Rotate tires if needed based on wear pattern and vehicle mileage.

Reassembly

1. Ensure all drain plugs, fill plugs, and filter housings are properly tightened and not leaking
2. Verify skid plate is reinstalled if it was removed
3. Confirm all wheels are properly torqued to specification
4. Double-check that oil fill cap is installed and engine bay is clean of tools

Verification

• Start engine and verify normal oil pressure within 5 seconds
• Allow engine to idle for 5 minutes and inspect all service points for leaks
• Check oil level on dipstick with engine off - should be at full mark
• Test drive vehicle for 10-15 minutes, checking transmission shift quality and listening for abnormal noises
• After test drive, recheck all fluid levels and inspect for leaks while engine is warm
• Verify fuel system priming was successful - engine should start normally without extended cranking
• Check that all warning lights on instrument cluster are functioning normally
• Record service in maintenance log with date, mileage, and all services performed

More procedures for this vehicle