Line Pressure Test

WARNING: This page is about a different variant/trim than selected.

Courtesy of FORD MOTOR COMPANY

NOTE: 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 the Stall Speed Test or further transmission damage will occur. Do not maintain WOT in any transmission range for more than 5 seconds.

This test verifies the line pressure is within specification.

1.

Connect the Transmission Fluid Pressure Gauge 307-004 (T57L-77820-A) to the line pressure tap.

2.

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

Pressure Chart

Gear	Line Pressure at Idle kPa (psi)		Line Pressure at WOT Stall kPa (psi)
Gear	Minimum	Maximum	Minimum	Maximum
P	303 kPa (44 psi)	483 kPa (70 psi)	303 kPa (44psi)	483 kPa (70 psi)
R	621 kPa (90 psi)	793 kPa (115 psi)	1, 655 kPa (240 psi)	2, 137 kPa (310 psi)
N	303 kPa (44 psi)	483 kPa (70 psi)	303 kPa (44 psi)	483 kPa (70 psi)
D	510 kPa (74 psi)	669 kPa (97 psi)	1, 586 kPa (230 psi)	1, 793 kPa (260 psi)
L	483 kPa (70 psi)	689 kPa (100 psi)	1, 586 kPa (230 psi)	1, 793 kPa (260 psi)

3.

If the line pressure is not within specification, see the Line Pressure Diagnosis Chart for line pressure concern causes.

4.

When the pressure tests are complete, install the line pressure tap plug.
- Tighten to 12 Nm (106 lb-in).

Line Pressure Diagnosis Chart

Test Results	Possible Source
HIGH at IDLE - ALL RANGES	Wiring Harness
LPC
Main Regulator Valve
LOW at IDLE - ALL RANGES	Low Transmission Fluid
Fluid Inlet Filter/Seal
Main Control Valve Body
Cross Leaks
Gaskets
Pump
Separator Plate
LOW in Park ONLY	Main Control Valve Body
LOW in Reverse ONLY	Separator Plate
Reverse Clutch
Main Control Valve Body
Forward Clutch
LOW in Neutral ONLY	Main Control Valve Body
LOW in Drive O/D ONLY	Forward Clutch
Main Control Valve Body
LOW in Manual Low ONLY	Forward Clutch
Main Control Valve Body