Nissan Pathfinder: VQ40DE Secondary Timing Chain Tensioner Failure

The VQ40DE 4.0-litre V6 uses a complex multi-stage timing chain system with secondary chain tensioners feeding the balance shaft and oil pump chains. The plastic ratchet clips and hydraulic tensioner bodies on these secondary chains are prone to early failure, allowing chain slack that causes the chain to jump teeth or contact the timing cover. Left unattended, the result is catastrophic internal engine damage — bent valves, damaged pistons, or complete engine seizure — as the camshaft timing is lost. The failure is strongly linked to extended oil change intervals and the use of incorrect viscosity oil, as tensioner hydraulics depend on adequate oil pressure from first start.

• Metallic rattling or slapping noise from the front of the engine on cold start, typically clearing within 5-10 seconds as oil pressure builds
• MIL illuminated with camshaft position or VVT timing fault codes (P0011, P0021, P0014, P0024)
• Rough running, misfires, or sudden engine failure in advanced cases where the chain has jumped timing

1. 1

   Cold-start the engine and listen for a metallic rattle or slapping sound from the front of the engine that clears after 3-10 seconds — this indicates tensioner lag.

2. 2

   Scan for fault codes P0011, P0021, P0014, or P0024 (camshaft position timing errors).

3. 3

   Check oil condition and change interval history; dark, degraded oil is a major risk factor.

4. 4

   Ask for evidence of the timing chain service (chain set, guides, and all tensioners) if the vehicle has covered more than 150,000 km.

Parts involved: Timing chain.

$3,500 to $12,000 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.

• “Has the timing chain, tensioners, and guides ever been replaced? Can you provide the service record?”
• “What oil viscosity and brand has been used, and how often was it changed?”
• “Does the engine make any ticking or rattling noise on cold start?”

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.