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When Servicing Full-Time 4WD Vehicles

WHEN SERVICING FULL-TIME 4WD VEHICLES

a. MEASURING POINTS FOR SPEEDOMETER TESTER

NOTE:
- Tester with a function of load setting cannot be used
- Inspection should be done in the front wheels.
- Do not start, accelerate nor decelerate the vehicle suddenly.
- Maximum vehicle speed must be below 60 km/h (when using free roller, it must be below 50 km/h).
- Driving time should be within 1 minute.







1. Place the front wheels onto the rollers.
2. Set the rear wheels free by free rollers or rigid racks.
3. Fasten the vehicle with the lock chain.
4. Start the engine, and then measure the vehicle speed by increasing the speed gradually in the D range.
5. After the measurement completion, decrease the vehicle speed by brake gradually, and then stop the vehicle.

b. MEASURING POINTS FOR BRAKE TESTER

NOTE:
- Tester with a function of load measurement cannot be used
- High-speed type brake cannot be used.

1. Place the wheels to be measured (front or rear) onto the rollers.
2. Shift the shift lever into neutral.
3. Perform the measurement by driving the tester rollers.

HINT: In case that the dragging force is over 10% of the load put on the axis, inspection of the wheel's rotating condition should be done with both of the left and right axes jacked up. If no abnormality is found in the rotating condition, adhesive torque of the viscous coupling causes the excessive dragging fore and therefore it means no problem exists in the vehicle.

c. MEASURING POINTS FOR ON-VEHICLE BALANCER




1. Jack up all 4 wheels with 2 post lift.
2. Fasten the vehicle by setting 2 pick-up stands in the bottom of suspension arm's tip of the front wheel 5 or rear wheels to be measured.
3. Support the vehicle with rigid racks so that vehicle will not lean in the vehicle's front/rear direction.
4. Release the parking brake.
5. Check that no dragging force exists by turning each wheel by hand.
6. Set the wheel balancers.
7. Measurement should be done by using both of engine drive and wheel balancer roller drive.

NOTE:
- Start the engine, and then increase the vehicle speed gradually in the D range.
- Do not accelerate nor decelerate suddenly.
- Deceleration should be done by brake gradually.
- Take special care that the vehicle does not move.
- Measurement should be done quickly.