Ford Ranger: P5AT 3.2 TDCi Water Pump Impeller Fracture

The P5AT 3.2 five-cylinder diesel uses a mechanical water pump with a plastic impeller that is prone to cracking and shedding fragments, abruptly stopping coolant circulation. Loss of coolant flow causes rapid engine overheating; if the driver does not pull over immediately, the cylinder head warps or the head gasket fails. Ford issued SSM 46609 acknowledging the defective impeller design and the replacement pump uses an updated metal impeller.

• Sudden temperature gauge climb to red zone without warning
• Coolant warning light illuminating with no visible external leak
• White steam from the bonnet vent in severe cases
• Coolant level repeatedly dropping between services
• Overheating specifically during low-speed or idling conditions when coolant flow demand is highest

1. 1

   Check coolant level on a cold engine and look for white milky residue under the radiator cap indicating head gasket compromise.

2. 2

   Ask for the service history to confirm whether the water pump has been replaced with the metal impeller variant.

3. 3

   On a test drive, watch the temperature gauge during stop-start city driving for any excursion above the midpoint.

Parts involved: Water pump.

$650 to $5,500 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 water pump ever been replaced, and if so, can you confirm the replacement used the updated metal impeller?”
• “Has the engine ever overheated, and has the cylinder head been pressure-tested or skimmed?”
• “Do you have service records confirming coolant system maintenance and any related head gasket work?”

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.