Line Pressure Test

4R70E/4R75E

Line Pressure Test

WARNING: If equipped with fire suppression system, refer to Fire Suppression System for Important Safety Warnings. Failure to follow this instruction may result in serious personal injury Procedures.

NOTICE: Carry out the Line Pressure Test prior to carrying out the Stall Speed Test. If the line pressure is low at stall, do not carry out Stall Speed Test or further transmission damage will occur. Do not maintain Wide Open Throttle (WOT) in any transmission range for more than 5 seconds. Stall Speed Test

This test verifies that the line pressure is within specification.

1. Connect Transmission Fluid Pressure Gauge to line pressure tap.

2. Start the engine and check line pressures. Refer to the Line Pressure Chart to determine if line pressure is within specification.

Line Pressure Chart:

3. Place the ignition switch in the OFF position. If line pressure is not within specification, check Electronic Pressure Control (EPC) pressure.

4. Connect Transmission Fluid Pressure Gauge to the EPC pressure tap.

5. Start the engine and check EPC pressure. Refer to the Line Pressure Chart for specifications.

6. If EPC pressure is not within specification, Go To Pinpoint Test E Pinpoint Test E: OSS Sensor to diagnose EPC operation. If EPC operation is OK, refer to the Line Pressure Diagnosis Chart for line pressure concern causes.

7. When the pressure tests are completed, install the pressure tap plugs.
- Tighten to 12 Nm (106 lb-in).

Line Pressure Diagnosis Chart: