Nissan Murano: Radiator Internal Partition Failure — CVT Fluid Contamination

The Murano radiator incorporates a transmission fluid cooler section separated from the coolant circuit by an internal plastic divider bonded to aluminium end tanks. Thermal cycling causes the plastic to crack or the bond to fail, allowing engine coolant and CVT fluid to cross-contaminate. Coolant entering the CVT circuit causes internal seals to swell and disintegrate and the push-belt to lose clamping pressure. The CVT is destroyed within a short period of driving in this condition. CVT fluid entering the coolant circuit foams the cooling system and can cause overheating. The failure is insidious because external fluid levels may appear normal until catastrophic damage has occurred.

• CVT fluid appearing pink, milky, or foamy on the dipstick or check-plug
• Coolant overflow reservoir showing oily film or discolouration
• CVT judder or loss of drive shortly after apparent normal operation
• Overheating warning with no obvious external coolant leak

1. 1

   Inspect the coolant overflow tank for oily sheen or brown emulsification.

2. 2

   The radiator end tanks should be inspected for cracks or delamination at the plastic-to-aluminium joints.

3. 3

   Ask for evidence that the original radiator has been replaced with an upgraded aluminium-core unit.

4. 4

   If a workshop inspection is possible: Remove the CVT fluid check-plug and inspect for milky or pink-tinted fluid indicating coolant ingress.

5. 5

   Remove the radiator cap when cold and check for oily residue on the underside.

Parts involved: Radiator.

$4,500 to $9,000 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 original radiator ever been replaced, and with what replacement unit?”
• “Has the CVT fluid ever shown any discolouration or been flushed after a radiator failure?”

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.