Stall Speed Test

WARNING: This page is about a different car, the 2009 Mercury Grand Marquis and 2009 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Block all wheels, set the parking brake and firmly apply the service brake to reduce the risk of vehicle movement during this procedure. Failure to follow these instructions may result in serious personal injury.

NOTE: Carry out Line Pressure Test prior to carrying out Stall Speed Test. If the line pressure is low at stall, do not carry out Stall Speed Test or further transmission damage will occur.

The Stall Speed Test checks the following:

Torque Converter Clutch (TCC) operation and installation
Holding ability of the forward clutch
Reverse clutch (the low-reverse bands)
Planetary One-Way Clutch (OWC)
Engine driveability

Conduct this test with the engine coolant and transmission fluid at correct levels and at normal operating temperature.

Apply the park brake firmly for each Stall Speed Test.

Find the specified stall RPM for the vehicle; refer to the STALL SPEED chart.

STALL SPEED

Application	Min.	Max.
4.6L 2V	2,065	2,409
4.6L Police applications	2,377	2,757

Connect a scan tool.

NOTE: If the engine RPM recorded by the scan tool exceeds the maximum limits, release the accelerator pedal immediately because clutch or band slippage is indicated.

In each of the following selector lever positions, R, Overdrive (Circle D), 2, 1 press the accelerator pedal to the floor and hold it just long enough to let the engine get to Wide Open Throttle (WOT). While conducting this test, do not hold the throttle plate open for more than 5 seconds at a time.
Note the results in each position.
After each position, move the selector lever to NEUTRAL and run the engine at 1,000 RPM for about 15 seconds to cool the torque converter before making the next test.
Refer to the STALL SPEED DIAGNOSIS CHART for corrective actions.

STALL SPEED DIAGNOSIS CHART

Selector Position	Stall Speeds High	Stall Speeds Low
Overdrive (Circle D)	Planetary One-Way Clutch (OWC)
Overdrive (Circle D), 2 and 1	Forward Clutch or Intermediate Clutch
R, Overdrive (Circle D), 2, 1	Carry Out Pressure Test	Torque Converter Stator OWC or Engine Driveability Concerns
R	Reverse Clutch or Low Reverse Band or Servo