Stall Speed Test

Stall Speed Test
This test checks operation of the following items:
^ Torque converter clutch (TCC)
^ Forward clutch
^ Low-one way clutch (OWC) assembly
^ Engine operation
^ Overdrive OWC assembly

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.

CAUTION: Always carry out the Line Pressure Test procedures prior to carrying out the Stall Speed Test. If line pressure is low at stall, do not carry out the Stall Speed Test or further transmission damage will occur. Line Pressure Test [1][2]Component Tests and General Diagnostics

CAUTION: After testing each of the following ranges D, 3, 2, 1 and R, move the transmission range selector lever to N and run the engine at 1,000 rpm for about 15 seconds to allow the torque converter to cool before testing the next range, otherwise transmission damage can occur.

CAUTION: Do not maintain wide open throttle (WOT) in any range for more than 5 seconds, otherwise transmission damage can occur.

CAUTION: If the engine rpm recorded by the scan tool exceeds maximum specified rpm, release the accelerator pedal immediately, otherwise transmission damage can occur. Clutch or band slippage is indicated.

NOTE: Prolonged use of this procedure may set DTC P0712, P1783. After carrying out Stall Speed Test, run OBD Test and Clear DTCs from memory.

NOTE: The Stall Speed Test should be carried out with the engine and transmission at normal operating temperatures.

1. Connect a scan tool to the vehicle.
2. Press the accelerator pedal to the floor (WOT) in each range. Record rpm reached in each range. Stall speeds should be as follows:

Stall Speed Chart:

Stall Speed Diagnosis Chart (Part 2):

If the stall speeds were too high, refer to the following Stall Speed Diagnosis Chart. If the stall speeds were too low, first check the engine idle speed. If the engine idle is OK, remove the torque converter and check the torque converter one-way clutch (OWC) for slippage.

Stall Speed Diagnosis Chart: