Road Test
Road TestINSPECTION
1. GENERAL PRECAUTION
Road tests should be conducted to properly diagnose the condition of automatic transmission.
NOTE: When performing the test, do not exceed posted speed limit.
2. D RANGE SHIFT FUNCTION
Check shifting between 1st <--> 2nd <--> 3rd 4th while driving on normal city streets.
3. D RANGE SHIFT SHOCK
Check the shock level when shifting up during normal driving.
4. KICK-DOWN FUNCTION
Check kick-down for each gear. Check the shock level during kick-down at the same time.
5. ENGINE BRAKE OPERATION
- Check the 3rd gear engine brake when shifting down from 4th to 3rd range while driving in 4th gear of manual mode [50 - 60 km/h (31 - 37 MPH)].
- Check the 2nd gear engine brake when shifting down from 3rd to 2nd range while driving in 3rd gear of manual mode [40 - 50 km/h (25 - 31 MPH)].
- Check the 1st gear engine brake when shifting down from 2nd to 1st range while driving in 2nd gear of manual mode [20 - 30 km/h (12 - 19 MPH)].
6. LOCK-UP FUNCTION
- When the accelerator is lightly depressed while driving on a flat road in "D" range, check that rpm does not change abruptly.
- Check slip lock-up with following procedure. Subaru Select Monitor is required for judgement.
Before starting the check, make sure that no DTC is displayed using the Subaru Select Monitor. If there is a DTC, perform the corrective action according to the DTC. Recheck to see that the DTC has been cleared, then start the slip lock-up check.
1. The check is to be performed on a flat and straight road or on a free roller.
NOTE:
- Slip lock-up will not operate when the vehicle is lifted up off of its wheels, since there is no surface resistance.
- When checking on the free roller, the driving resistance will be slightly inadequate. It will be easier to judge if the foot brake is lightly applied while performing the check.
2. Connect the Subaru Select Monitor.
3. Check the ATF temperature using the Subaru Select Monitor.
NOTE:
- Make sure that the ATF temperature is between 50 - 100°C (122 - 212°F).
- If the temperature is low, warm up the ATF by running the vehicle.
4. Start the engine, so that the lock-up duty can be read on the data display of the Subaru Select Monitor.
5. Drive the vehicle at a constant speed of 35 - 40 km/h (22 - 25 MPH).
6. Read the lock-up duty while vehicle is running.
Standard: 25-45%
NOTE:
- The reading maybe slightly lower on a free roller.
- Slip lock-up control is not operating if the lock-up duty is 5% or less, or when the lock-up duty goes down immediately after starting to rise. In these cases, improper ATF or deterioration of the ATF may be the cause. Check the amount of ATF or replace the fluid, then recheck.
7. P RANGE OPERATION
Stop the vehicle on an uphill grade of 5% or more and shift to the "P" range. Check that the vehicle does not move when the parking brake is released.
8. NOISE AND VIBRATION
Check for noise and vibration while driving and during shifting.
9. TRANSFER CLUTCH
Check for tight corner braking phenomenon when the vehicle is moved forward with the steering fully turned.
10. OIL LEAKAGE
After the driving test, inspect for oil leaks.
Stall Test
INSPECTION
NOTE: The stall test is extremely important in diagnosing the condition of an automatic transmission and engine. The test is necessary to measure the engine stall speeds in "R" and "2nd of manual mode".
Purposes of the stall test:
- Operational check of the automatic transmission clutch
- Operational check of the torque converter clutch
- Engine performance check
1. Check that the throttle valve fully opens.
2. Check that the engine oil level is correct.
3. Check that the coolant level is correct.
4. Check that the ATF level is correct.
5. Check that the differential gear oil level is correct.
6. Increase the ATF temperature to 70 to 80°C (158 to 176°F) by idling the engine for approximately 30 minutes (with select lever set to "N" or "P").
7. Place the wheel chocks at the front and rear of all wheels and apply the parking brake.
8. Move the manual linkage to ensure it operates properly, and then set to the "2nd gear of manual mode".
9. While pressing hard on the foot brake pedal, slowly depress the accelerator pedal to full throttle.
10. When the engine speed stabilizes, quickly record the engine speed and release accelerator pedal.
11. Shift the select lever to "N" range, and cool down the engine by idling it for one minute or more.
12. If the stall speed in "2nd gear of manual mode" is higher than specifications, low clutch slipping and 2-4 brake slipping may occur. To identify this, conduct the same test as above in "R" range.
13. Perform the stall tests with the select lever in "D" range.
NOTE:
- Do not continue the stall test for 5 seconds or more at a time (from closed throttle, fully open throttle to stall speed reading). Failure to follow this instruction will cause the engine oil and ATF to deteriorate and the clutch and brake to be adversely affected.
- Be sure to cool down the engine for at least one minute after each stall test with the select lever set in the "P" or "N" range and with the idle speed of 1,200 rpm or less.
- If the stall speed is higher than the specified range, attempt to finish the stall test in as short a time as possible, in order to prevent the automatic transmission from sustaining damage.
Stall speed (at sea level): 2,200 - 2,700 rpm
Time Lag Test
INSPECTION
NOTE: When the select lever is shifted while the engine is idling, there will be a certain time elapse or lag before shock is felt. This is used for checking the condition of the low clutch, reverse clutch, low & reverse brake and one-way clutch.
- Perform the test at normal operation fluid temperature of 70 - 80°C (158 - 176°F).
- Be sure to allow a one minute or more interval between tests.
- Make three measurements and take the average value.
1. Fully apply the parking brake.
2. Start the engine.
Check the idle speed (A/C OFF).
3. Shift the select lever from "N" to "D" range.
Using a stop watch, measure the time which takes from shifting the lever until the shock is felt.
Time-lag
Standard. 1.2 seconds or less
If "N" -> "D" time lag is longer than specified:
- Line pressure too low
- Low clutch worn
- One-way clutch not operating properly
- D-ring worn
4. In the same manner, measure the time lag of "N" -> "R".
Time-lag
Standard. 1.5 seconds or less
If "N" -> "R" time lag is longer than specified:
- Line pressure too low
- Reverse clutch worn
- Low & reverse brake worn
- D-ring worn
Line Pressure Test
MEASUREMENT
NOTE: If the clutch or brake shows a signs of slipping or shift feel is not correct, check the line pressure.
- Excessive shock during up-shift or if shifting takes place at a higher point than for normal conditions, this may be due to the line pressure being too high.
- Slippage or inability to operate the vehicle may, in most cases, be due to insufficient oil pressure for the operation of clutch, brake or control valve.
1. Line pressure measurement (under no load):
1. Before measuring line pressure, lift up the vehicle.
2. Maintain the ATF temperature at approx. 70 - 80°C (158 - 176°F) during measurement. (ATF will reach the temperature above after idling the engine for approx. 30 minutes with the select lever in "N" or "P".)
2. Line pressure measurement (under heavy load.
1. Before measuring line pressure, apply both the foot and parking brakes with all wheels chocked on both front and rear of all wheels. (Same conditions as for a stall test)
2. Measure the line pressure when the select lever is in "R" or 2nd of manual mode with engine under stall conditions.
3. Measure the line pressure within 5 seconds after shifting the select lever to each position. (If the line pressure needs to be measured again, allow the engine to idle and cool it down for more than 1 minute.)
4. Maintain the ATF temperature at approx. 70 - 80°C (158 - 176°F) during measurement. (ATF will reach the temperature above after idling the engine for approx. 30 minutes with the select lever in "N" or "P".)
3. Remove the test plug and attach the ST instead.
ST 498897200 OIL PRESSURE GAUGE ADAPTER
4. Connect the ST1 with ST2.
ST1 498897200 OIL PRESSURE GAUGE ADAPTER
ST2 498575400 OIL PRESSURE GAUGE ASSY
5. Check for duty ratio changes by adjusting the acceleration pedal position using the Subaru Select Monitor.
6. Remove the ST and install the test plug.
Tightening torque: 13 N-m (1.3 kgf-m, 9.6 ft-lb)
Transfer Clutch Pressure Test
INSPECTION
Check the transfer clutch pressure in accordance with the following chart in the same manner as line pressure.
ST 498897700 OIL PRESSURE ADAPTER SET
ST 498575400 OIL PRESSURE GAUGE ASSY
NOTE:
- Before setting to FWD mode, install the spare fuse on the FWD mode switch.
- If no oil pressure is produced or if it does not change in AWD mode, there may be a problem in the transfer duty solenoid or control valve body.
- If oil pressure is produced in FWD mode, there is the same problem as the AWD mode.
