Transmission Fluid Pump

Driven directly by the engine through the torque converter, this pump generates every bit of pressure the transmission uses — to apply clutches, to lock the converter, to lubricate and to carry heat to the cooler. Because it is engine-driven rather than electric, it produces least pressure exactly when the engine is idling, which is why a tiring pump shows itself first as delayed engagement when selecting drive after the vehicle has been standing. Wear is gradual, so the resulting slip is easy to attribute to worn clutches instead — and measuring line pressure with a gauge is what separates the two.

Also known as: atf pump, transmission pump, front pump, gearbox oil pump

Referenced by 22 codes

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Codes involving this component (22)

Other components in Transmission

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