Stall Speed Test

The Stall Speed Test checks:

• 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 concerns.

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.

1. Find the specified stall rpm for the vehicle, see the STALL SPEED TABLE . Use a grease pencil to mark the rpm on the dial of a tachometer.
   STALL SPEED
   
   

   Engine	rpm
   3.5L	1,878-2,678

2. Connect a scan tool.
NOTE: If the rpm recorded by the scan tool exceeds the maximum limits, release the accelerator pedal immediately because clutch or band slippage is indicated.
3. In each of the following range REVERSE, DRIVE and LOW, press the accelerator pedal to the floor and hold it just long enough to let the engine get to Wide Open Throttle (WOT). Do not hold the throttle open for more than 5 seconds at a time.
4. Note the results in each range.
5. After each range, move the selector lever to NEUTRAL and run the engine at 1,000 rpm for about 15 seconds to cool the torque converter before the next test.
6. Use the stall speed diagnosis table for corrective actions.
NOTE: The stall speed in REVERSE will be lower.
7. If stall speeds were too high, see the STALL SPEED TABLE . If stall speeds were too low, first check engine idle speed and tune up. If engine is OK, remove torque converter and check TCC  for slippage.