Stall Test

The object of this test is to check the overall performance of the transmission and engine by measuring the stall speeds in the D and R ranges.

NOTICE:

• Perform the test at normal operating fluid temperature (50 - 80°C or 122 - 176°F).

• Do not continuously run this test longer than 5 seconds.

• To ensure safety, conduct this test in a wide, clear, level area, which provides good traction.

• The stall test should always be carried out in pairs. One should observe the conditions of wheels or wheel stoppers outside the vehicle while the other is performing the test.

MEASURE STALL SPEED

(a) Chock the four wheels.

(b) Connect a tachometer to the engine.

(c) Fully apply the parking brake.

(d) Keep your left foot pressed firmly on the brake pedal.

(e) Start the engine.

(f) Shift into the D range. Step all the way down on the accelerator pedal with your right foot. Quickly read the stall speed at this time.

NOTICE: Release the accelerator pedal and stop test if the rear wheels begin to rotate before the engine speed reaches specified stall speed.

Stall speed: 7M-GE 2,200 ± 150 rpm 7M-GTE 2,500 ±150 rpm

(g) Perform the same test in R range, EVALUATION

(a) Usually the rear wheels begin to rotate when the engine speed (depending on the brake force) reaches approximately 1,800 — 1,900 rpm. If so, the stall speed may be within the standard range. As a result, it can be assumed that there are no problems regarding the stall test explained in the following (b), (c), (d) and (e).

(b) If the stall speed is the same for both ranges without the rear wheels rotating but lower than specified value:

• Engine output may be insufficient

• Stator one-way clutch is not operating properly

HINT: If more than 600 rpm below the specified value, the torque converter could be faulty.

(c) If the stall speed in D range is higher than specified without the rear wheels rotating:

• Line pressure too low

• Forward clutch slipping

• No. 2 one-way clutch not operating properly

• O/D one-way clutch not operating properly

(d) If the stall speed in R range is higher than specified without the rear wheels rotating:

• Line pressure too low

• Direct clutch slipping

• First and reverse brake slipping

• O/D one-way clutch not operating properly

(e) If the stall speed in both R and D ranges are higher than specified without the rear wheels rotating:

• Line pressure too low

• Improper fluid level

• O/D one-way clutch not operating properly

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