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Stall Speed Test

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

Warning:
^ Apply the parking brake firmly while carrying out each stall test. Failure to follow these instructions may result in personal injury.


Caution:
^ Always carry out line pressure test procedures prior to carrying out the stall speed test. if line pressure is low at stall, do not carry out stall speed test or further transmission damage will occur.


Note:
^ The stall speed test should be carded out with the engine and transmission at normal operating temperatures.

1. Connect tachometer to the engine.

Caution:
^ After testing each of the following ranges D, 2, 1, and R, move the transmission range selector lever to N (NEUTRAL) and run engine at 1,000 rpm for about 15 seconds to allow the torque converter to cool before testing the next range.


Caution:
^ Do not maintain wide open throttle in any range for more than five (5) seconds.


Caution:
^ If the engine rpm recorded by the tachometer exceeds maximum specified rpm, release the accelerator pedal immediately. Clutch or band slippage is indicated.


Note:
^ Prolonged use of this procedure may set diagnostic trouble code (DTC) P0712 or P1783. After carrying out stall speed test run OBD test and clear DTCs from memory.

2. Press accelerator pedal to floor (WOT) in each range. Record rpm reached in each range. Stall speeds should be as follows:

Stall Speed Chart:





If stall speeds were too high, see the stall speed diagnosis chart. If stall speeds were too low, first check the engine idle speed. If engine idle is OK, remove torque converter and check the torque converter clutch for slippage.

Stall Speed Diagnosis Chart: