Subaru Legacy III (2000-2003 year). Manual - part 535

AT-34

AUTOMATIC TRANSMISSION

STALL TEST

3. EVALUATION

Stall speed (at sea level)

Position

Cause

Less than specifications

2 (Hold switch ON)

R

• Throttle valve not fully open
• Erroneous engine operation 
• Torque converter clutch's one-way clutch slipping

Greater than specifications

D

• Line pressure too low
• Low clutch slipping
• One-way clutch malfunction

R

• Line pressure too low
• Reverse clutch slipping
• Low & reverse brake slipping

2 (Hold switch ON)

• Line pressure too low
• Low clutch slipping
• 2-4 brake slipping

AT-35

AUTOMATIC TRANSMISSION

TIME LAG TEST

6. Time Lag Test

A: INSPECTION

1. GENERAL INFORMATION

If the select lever is shifted while the engine is
idling, there will be a certain time elapse or lag be-
fore the shock can be felt. This is used for checking
the condition of the low clutch, reverse clutch, low &
reverse brake and one-way clutch.

NOTE:
• Perform the test at normal operating fluid tem-
perature 70 to 80

°

C (158 to 176

°

F).

• Be sure to allow a 1 minute interval between
tests.
• Make three measurements and take the average
value.

2. TEST METHODS

1) Fully apply the parking brake.
2) Start the engine.
Check the idling speed (A/C OFF). 
3) Shift the select lever from “N” to “D” range.
Using a stop watch, measure the time it takes from
shifting the lever until the shock is felt.

Time lag: Less than 1.2 seconds

4) In the same manner, measure the time lag for
“N” 

→

 “R”.

Time lag: Less than 1.5 seconds

3. EVALUATION

1) If “N” 

→

 “D” time lag is longer than specified:

• Line pressure too low
• Low clutch worn
• One-way clutch not operating properly
2) If “N” 

→

 “R” time lag is longer than specified:

• Line pressure too low
• Reverse clutch worn
• Low & reverse brake worn

AT-36

AUTOMATIC TRANSMISSION

LINE PRESSURE TEST

7. Line Pressure Test

A: MEASUREMENT

1. GENERAL INFORMATION

If the clutch or the brake shows a sign of slippage or
shifting sensation is not correct, the line pressure
should be checked.
• Excessive shocks during upshifting or shifting
takes place at a higher point than under normal cir-
cumstances, may be due to the line pressure being
too high.
• Slippage or inability to operate the vehicle may,
in most cases, be due to loss of oil pressure for the
operation of the clutch, brake or control valve.
1) Line pressure measurement (under no load)

NOTE:
• Before measuring the line pressure, jack-up all
wheels.
• Maintain the temperature of ATF at approx. 70 —
80

°

C (158 — 176

°

F) during measurement.

(ATF will reach the above temperature after idling
the engine for approx. 30 minutes with select lever
in “N” or “P”.)
2) Line pressure measurement (under heavy load)

NOTE:
• Before measuring the line pressure, apply both
foot and parking brakes with all wheels chocked
(Same as for “stall” test conditions).
• Measure the line pressure when select lever is in
“R”, “2” with engine under stall conditions.
• Measure the line pressure within 5 seconds after
shifting the select lever to each position. (If line
pressure needs to be measured again, allow the
engine to idle, and then stop it to cool down for at
least one minute.)
• Maintain the temperature of ATF at approx. 70 —
80

°

C (158 — 176

°

F) during measurement (ATF will

reach the above temperature after idling the engine
for approx. 30 minutes with the select lever in “N” or
“P”.)

2. TEST METHODS

1) Temporarily attach the ST to a suitable place in
the driver's compartment, remove the blind plug lo-
cated in front of the toe board and pass the hose of
the ST to engine compartment.
ST

498575400

OIL PRESSURE GAUGE 
ASSY

2) Remove the test plug and install the ST instead.
ST

498897200

OIL PRESSURE GAUGE 
ADAPTER

3) Connect the ST1 with ST2.
ST1

498897200

OIL PRESSURE GAUGE 
ADAPTER

ST2

498575400

OIL PRESSURE GAUGE 
ASSY

(A) Pressure gauge hose

(B) Hole in toe board (blank cap hole)

(C) Brake pedal

(A) Test plug

AT-00019

( C )

( B )

( A )

AT-00675

( A )

AT-37

AUTOMATIC TRANSMISSION

LINE PRESSURE TEST

4) Check for duty ratio changes by opening and
closing the throttle valve using Subaru Select Mon-
itor.

(1) Insert the cartridge to Subaru Select Moni-
tor. <Ref. to AT-19, PREPARATION TOOL,
General Description.>

(2) Connect the Subaru Select Monitor to data
link connector.

5) Check the line pressure in accordance with the
following chart.

3. EVALUATION

Standard line pressure

Range 

position

Line pres-

sure duty 

ratio (%)

Throttle 
position

Line pressure

kPa (kg/cm

2

, psi)

2

5

Full open

1,128 — 1,304 

(11.5 — 13.3, 

164 — 189)

R

5

Full open

1,520 — 1,716

(15.5 — 17.5, 

220 — 249)

D

95

Full closed

304 — 412 

(3.1 — 4.2, 44 — 60)

AT-00339