Stall Speed Test

WARNING: Apply the parking brake firmly while carrying out each stall test.

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

The stall speed test checks:
- torque converter clutch operation and installation.
- holding ability of the forward clutch.
- reverse clutch (the low-reverse bands).
- planetary one-way clutch.
- Driveability Concerns.

Conduct this test with the engine coolant and transmission fluid at proper levels and at normal operating temperature.
Apply the parking brake firmly for each stall speed test.
1. Find the specified stall rpm for the vehicle. Refer to the Stall Speed Chart. Use a grease pencil to mark the rpm on the dial of a tachometer.





Stall Speed Chart

2. Connect a tachometer to the engine.

3. Note: If the rpm recorded by the tachometer exceeds the maximum limits, release the accelerator pedal immediately because clutch or band slippage is indicated.

In each of the following ranges (D), D, 2, 1, R, press the accelerator pedal to the floor and hold it just long enough to let the engine get to Wide Open Throttle (WOT). While making this test, do not hold the throttle open for more than five 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 1000 rpm for about 15 seconds to cool the torque converter before making the next test.
6. Refer to the chart for corrective actions.





Stall Speed Diagnosis Chart

7. Note: The stall speed in REVERSE will be lower.

If stall speeds were too high, refer to the chart. If stall speeds were too low, first check engine idle speed and tune-up. If engine is OK, remove torque converter and check torque converter clutch for slippage.