Differential Fluid Change - Rear

Drain and refill the rear differential with fresh 75W-90 synthetic gear oil to maintain proper lubrication and extend differential service life.

Warnings

Tools required

Parts

• Rear differential fill plug gasket/washer × 1 — Use OEM specification
• Rear differential drain plug gasket/washer × 1 — Use OEM specification

Fluids

• 75W-90 synthetic gear oil — 2.75 qt

Preparation

1. Park vehicle on level ground and engage parking brake.
2. If vehicle has been driven, allow differential to cool for at least 30 minutes.
3. Raise vehicle using a lift or jack stands rated for the vehicle's weight, ensuring it is level side-to-side for accurate fill level.
4. Verify you have the correct 75W-90 synthetic gear oil and new drain/fill plug gaskets before beginning.

Procedure

1. 1

   Locate differential drain and fill plugs
   Position yourself under the rear of the vehicle. The rear differential is a chassis-mounted final drive unit located at the center of the independent rear suspension, connected to the wheels via halfshafts rather than a solid axle. Identify the fill plug and drain plug on the differential housing per the factory service manual; the fill plug is typically located on the side of the housing and the drain plug on the lowest point of the housing. Verify exact locations against the FSM. Clean the area around both plugs with a wire brush or rag to prevent debris from entering during service.
2. 2

   Loosen fill plug first
   Using the correct hex/square plug tool (verify size against the FSM) and a 3/8" ratchet with extension, loosen the fill plug approximately 2-3 turns but do NOT remove it yet. This verifies you can access the fill plug before draining; if the fill plug is seized, you can still drive the vehicle to address the issue rather than being stranded with an empty differential.
3. 3

   Position drain pan and remove drain plug
   Place the drain pan directly beneath the differential drain plug. Using the 10mm hex socket and ratchet, slowly loosen the drain plug. Once loose, carefully unthread it by hand for the final few turns, pulling it away quickly once fully removed to avoid fluid running down your arm. Allow all fluid to drain completely; this typically takes 5-10 minutes for full drainage.
4. 4

   Inspect drained fluid and drain plug
   While fluid is draining, inspect the drain plug magnet (if equipped) for metal shavings or debris. Minor fine metallic dust is normal; large chunks or excessive material may indicate wear issues requiring further inspection. Observe the drained fluid color and consistency; it should be translucent amber to brown. Milky appearance indicates water contamination; metallic sparkles or gritty texture indicates excessive wear.
5. 5

   Clean and reinstall drain plug
   Clean the drain plug threads and magnet thoroughly with a shop rag. Inspect the drain plug gasket/washer and replace with a new one. Thread the drain plug in by hand initially to avoid cross-threading, then tighten with the 10mm hex socket. Tighten firmly to the factory torque specification (verify exact value in the FSM before final tightening).
6. 6

   Remove fill plug completely
   Fully remove the fill plug you loosened in Step 2. Remove and inspect the fill plug gasket/washer; replace with a new one. Set the fill plug aside in a clean location where it will not roll away.
7. 7

   Fill differential with gear oil
   Using a fluid pump or squeeze bottle with appropriate nozzle, insert the fill tube into the fill plug hole. Slowly pump the FSM-specified synthetic gear oil (verify correct viscosity, e.g., 75W-90 or 75W-140, and required limited-slip friction modifier) into the differential. The correct fill level is reached when oil begins to seep out of the fill hole. The correct fill quantity should be verified against the factory service manual; regardless of stated capacity, the differential is properly filled when oil begins to seep out of the fill hole with the vehicle level. Fill slowly to avoid overflow and allow air to escape; the process takes 3-5 minutes.
8. 8

   Reinstall fill plug
   Once gear oil reaches the bottom of the fill plug hole and begins to seep out, wait a moment for the level to stabilize. Thread the fill plug with new gasket/washer in by hand, then tighten with the 10mm hex socket. Tighten firmly to the factory torque specification for the fill plug (verify exact value in the FSM before final tightening).
9. 9

   Clean differential housing and inspect for leaks
   Wipe down the differential housing exterior with shop rags to remove any spilled gear oil. Inspect both the drain and fill plugs for any signs of seepage. The plugs should be completely dry with no fluid weeping from the threads.

Reassembly

1. Lower vehicle to the ground if raised on a lift or jack stands.
2. Dispose of used gear oil properly at a recycling center or parts store that accepts used fluids; do not pour down drains or on the ground.

Verification

• Start the vehicle and allow it to idle for 30 seconds, then take a short test drive (1-2 miles) at various speeds to circulate the new fluid.
• After the test drive, re-inspect the drain and fill plugs for any signs of leakage while the vehicle is on level ground.
• Listen for any unusual noises from the rear differential during the test drive; the differential should operate quietly with smooth power delivery.
• Check the ground under the vehicle after it has been parked for several hours to confirm no drips are present.

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle