Info - Diagnostic Tips for Vibration/Shake Felt in Steering Wheel/Column Area, Drivers Seat, Rear Floor Area While Driving at Highway Speeds of 72 km/h - 120 km/h (45 mph - 75 mph)

This bulletin will address three POSSIBLE factors that may influence a smooth road vibration/shake experienced in the Terraza van with independent rear suspension. These are not the only three possibilities that may cause a vehicle vibration/shake. This bulletin is designed to be a diagnostic aid and NOT a specific repair guideline.

The vibration that may be felt in the steering wheel/column, driver’s seat and/or in the rear floor pan may come from a combination of suspension and I/P fasteners, tires that exhibit high radial force variation and/or rear wheel bearings that have high lateral runout.

Inspect the tire and wheel assemblies for excessive radial force variation as outlined in Service Bulletin #00-03-10-006A (or newer) -- Information on Tire Radial Force Variation (RFV).

It is critical that when working on the Terraza van with independent rear suspension that the two tire/wheel assemblies with the least amount of radial force variation be installed on the rear of the vehicle to minimize a vibration/shake condition.

It is possible that a rear bearing hub assembly may have excessive lateral runout, end play, or wheel stud runout that can cause a vibration/shake condition on smooth road surface. Follow the procedure below to check lateral runout in the rear bearing hub assemblies.

Wheel Bearings Diagnosis

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Remove the tire and wheel. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.

Important: Support the vehicle by the lower control arms to prevent movement during wheel bearing/hub inspection.

3. Mount and secure the J-8001 Dial Indicator to the steering knuckle.
4. Firmly push the hub flange towards the vehicle.
5. Ensure that the dial indicator contacts the vertical surface of the hub as close as possible to the center of the flange.
6. Firmly pull the hub flange away from the vehicle in order to inspect the total travel indicator by the dial indicator.
7. The rear wheel bearing lateral runout should be less than 0.127 mm (0.005 in).

Brake Rotor Assembled Lateral Runout (LRO) Measurement

Important: 

•	Brake rotor assembled lateral runout (LRO) exceeding the maximum allowable specification can cause thickness variation to develop in the brake rotor over time, usually between 4 800-11 300 km (3,000-7,000 mi).

•	Brake rotor thickness variation MUST be checked BEFORE checking for assembled LRO. Thickness variation exceeding the maximum acceptable level can cause brake pulsation. Refer to Brake Rotor Thickness Variation Measurement .

1. Matchmark the position of the brake rotor to the wheel studs if this has not been done already.

Important: Whenever the brake rotor has been separated from the hub/axle flange, any rust or contaminants should be cleaned from the hub/axle flange and the brake rotor mating surfaces. Failure to do this may result in excessive assembled LRO of the brake rotor, which could lead to brake pulsation.

2. Inspect the mating surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles, corrosion, rust, or debris remaining. If the wheel hub/axle flange and/or if the brake rotor mating surfaces exhibit these conditions, perform the following steps:

•	Remove the brake rotor from the vehicle.

•	Using the J-42450-A , thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange.

•	Using the J-41013 , thoroughly clean any rust or corrosion from the mating surface of the brake rotor.

•	Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.

3. Install the rotor to the hub/axle flange using the matchmark made prior to removal.
4. Hold the rotor firmly in place against the hub/axle flange and install one of the J-45101-100 (1), and one lug nut (2) onto the upper-most wheel stud.
5. Continue to hold the rotor secure and tighten the lug nut firmly by hand.
6. Install the remaining J-45101-100 and lug nuts onto the wheel studs and tighten the nuts firmly by hand in a star-pattern.
7. Using the J-39544-KIT , or equivalent, tighten the lug nuts in a star-pattern to specification, in order to properly secure the rotor. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
8. If the brake rotor has been REFINISHED or REPLACED with a new rotor, proceed to step 14.
9. If the brake rotor meets the following criteria, proceed to step 10.

•	The rotor is within specifications and is being REUSED.

•	The rotor has NOT been refinished.

•	The rotor does NOT exhibit thickness variation exceeding the maximum allowable level.

10. Mount a dial indicator, J-45101 , or equivalent, to the steering knuckle and position the indicator button so it contacts the brake rotor friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the rotor.
11. Measure and record the assembled LRO of the brake rotor.

•	Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero.

•	Rotate the rotor until the highest reading is displayed on the dial.

•	Mark the location of the high spot relative to the nearest wheel stud, or studs.

•	Measure and record the amount of LRO.

12. Compare the brake rotor assembled LRO to the following specification:

Specification
Rear brake rotor maximum allowable assembled lateral runout: 0.06 mm (0.002 in)

13. If the brake rotor assembled LRO is within specifications, proceed to step 18. If the brake rotor assembled LRO exceeds the specification, refinish the rotor to ensure true parallelism, refer to Brake Rotor Refinishing . After refinishing the rotor, proceed to step 14.
14. Mount a dial indicator, J-45101 , or equivalent, to the steering knuckle and position the indicator button so it contacts the brake rotor friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the rotor.
15. Measure and record the assembled LRO of the brake rotor.

•	Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero.

•	Rotate the rotor until the highest reading is displayed on the dial.

•	Mark the location of the high spot relative to the nearest wheel stud, or studs.

•	Measure and record the amount of LRO.

16. Compare the brake rotor assembled LRO to the following specification:

Specification
Rear brake rotor maximum allowable assembled lateral runout: 0.06 mm (0.002 in)

17. If the brake rotor assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to Brake Rotor Assembled Lateral Runout (LRO) Correction .
18. If the brake rotor assembled LRO measurement is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the J-45101-100 and the lug nuts.

Hub/Axle Flange and Wheel Stud Runout Inspection

1. Mark the location of the wheels to the wheel studs and mark the specific vehicle position on each tire and wheel - LF, LR, RF, RR.
2. Remove the tire and wheel assemblies from the vehicle. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
3. Remove the brake rotors from the vehicle. Clean the mounting surfaces of the brake rotors and the hub/axle flanges of any loose debris, rust, and corrosion. Refer to Brake Rotor Replacement - Front and Brake Rotor Replacement - Rear in Disc Brakes.
4. Position the J-8001 , or equivalent, on the machined surface of the wheel hub/axle flange outside of the wheel studs.
5. Rotate the hub one complete revolution in order to find the low spot.
6. Set the J-8001 , or equivalent, to zero at the low spot.
7. Rotate the hub one more complete revolution and measure the total amount of wheel hub/axle flange runout.

Specification - Guideline
Rear Wheel hub/axle flange runout tolerance guideline: 0.06 mm (0.0023 in).

8. If the runout of the wheel hub/axle flange IS within specification, proceed to step 12.
9. If the runout of the wheel hub/axle flange is marginal, the wheel hub may or may not be the source of the disturbance.
10. If the runout of the wheel hub/axle flange is excessive, replace the wheel hub/axle flange. Measure the runout of the new wheel hub/axle flange. Refer to the appropriate procedure.
11. Position the J-8001 , or equivalent, in order to contact the wheel mounting studs. Measure the stud runout as close to the flange as possible.
12. Turn the hub one complete revolution to register on each of the wheel studs.
13. Zero the J-8001 , or equivalent, on the lowest stud.
14. Rotate the hub one more complete revolution and measure the total amount of wheel stud - stud circle - runout.

Specification - Guideline
Wheel stud runout tolerance guideline: 0.254 mm (0.010 in)

15. If the runout of the wheel studs - stud circle - is marginal, the wheel studs may or may not be contributing to the disturbance.
16. If the runout of the wheel studs - stud circle - is excessive, replace the wheel studs as necessary. Measure the runout of the new wheel studs. Refer to the appropriate procedure:

It is possible that a vibration/shake condition may be amplified if certain torque specifications are at the low end of the torque specification. Torque specifications should be checked on the following components if a vibration/shake concern is still present after the tires and bearings have been inspected.