Nissan Navara: D22 and D40 Rear Differential Pinion and Axle Oil Seal Weeping

Both the D22 and D40 Navara use a conventional solid rear axle with hypoid bevel gear differential. The pinion oil seal (at the front of the differential where the propeller shaft connects) and the inner axle shaft seals are known to weep gear oil over time, particularly once odometer readings pass 150,000 km. Weeping pinion seals contaminate the rear brakes — a safety-critical failure mode — while axle seal leaks allow gear oil to saturate the brake drum linings, significantly reducing braking performance.

• Gear oil residue or wet film visible on the rear axle housing near brake drum or at the differential pinion flange
• Rear brake fade or pulling to one side under braking — indicating oil-contaminated brake shoes
• Differential oil level low on check with no visible pooling under the vehicle
• Burning gear oil smell from the rear of the vehicle after driving

1. 1

   Check both ends of the rear axle housing where the axle shafts emerge — fresh gear oil here indicates failed shaft seals.

2. 2

   Remove a rear brake drum and inspect the shoes for oil contamination (shiny, saturated, or discoloured lining material indicates seal failure).

3. 3

   If a workshop inspection is possible: With the vehicle on a hoist, inspect the pinion seal where the rear propeller shaft flange meets the differential nose for gear oil weeping or residue.

Parts involved: Differential.

$200 to $700 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Have the rear differential pinion or axle shaft seals ever been replaced?”
• “When were the rear brake shoes last inspected or replaced, and was any oil contamination found?”
• “Is there any gear oil residue visible around the rear axle housing or differential?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.