Service
For Service AdvisorIt is critical to address all of the points listed in order to ensure that the conditions observed during the test drive are valid concerns.
1. Ask customer appropriate questions based on attached questionnaires. Enter all information and attach copies to Repair Order.
2. Check tire pressures, which must be set according to what is recommended in the Owner's Manual. (Use Bartec TPMS tool (BRT-DBL4) to check current tire pressures. Record on Repair Order and questionnaire.)
3. Check wheels and tires for any damage.
4. Make sure that Audi-approved wheels and tires are installed. (See Owner's Manual.)
5. Always address any concerns with the customer prior to further diagnosis.
6. Test drive vehicle with customer to verify vibration complaint.
7. Continue with Technician test drive.
Technician test drive
1. Check tire pressures, which must be set according to what is recommended in the Owner's Manual. (Record on Repair Order and questionnaire)
2. Check wheels and tires for any damage.
3. Check suspension and steering components for damage.
4. Make sure that Audi-approved wheels and tires are installed. (See Owner's Manual)
5. Always address any concerns with the customer prior to further diagnosis.
6. Warm tires by driving the vehicle for at least 20 miles (32 km) over various speed ranges (including highway driving at speeds greater than 55 mph / 88 kph). Tires must be warm in order for the test drive to be effective since cold tires may produce a vibration due to temporary flat spotting. (See Flat spots section below)
7. If vibration no longer exists, advise customer of flat spotting.
Flat spots
After a stationary period of only a few hours, flat spots are created as the warm tire cools down. Depending on the type, size and make of the tire, flat spots may appear more often. See information on flat spots in the Repair Manual under Suspension, Wheels, Steering >> Wheel and Tire Guide >> 44 Wheels, Tires, Wheel Alignment >> Diagnosis and Testing >> Wheel and Tire Vibration >. Tire Flat Spots from Standing.
Tip: Flat spots are normal and no replacement of tires is necessary.
1. Flat spots falsify the radial force variation and must be driven out before balancing the wheel. Complete a test drive of at least 20 miles (32km) over various speed ranges (including highway driving at speeds greater than 55 mph /88 kph).
2. Immediately after the test drive, raise vehicle to prevent temporary flat spotting and check road force and balance of each tire using VAS 6230(A) Hunter vibration control unit (GSP9700) or similar. Remove and balance the wheels immediately following the test drive. On cooled-down tires, flat spots may reappear.
3. If vibration exists, reduce the radial force variation.
Effects of Increased radial Forces on the Vehicle
Measure and reduce the radial force variation
1. Optimize the radial forces on a VAS 6230(A) Hunter vibration control unit (GSP9700 Road Force Measurement(R)) or similar tool.
When tightening the wheel on the balancing machine, make sure the contact surfaces of flange and wheel are clean, the wheel is correctly centered, and a suitable cone and clamping plate are used.
Note:
It is mandatory to use the five-finger clamping plate (VAS 6243 or similar) when mounting wheels to avoid damage of wheels and for proper balancing.
2. Set the tire pressure of every wheel to 2.5 bar (36 PSI).
3. Ensure the VAS 6230(A) or Hunter GSP9700 is set to proper road force limits as shown in the attached document GSP 9700 Operation Manual_P104_105.
4. Ensure that the machine is properly anchored to the floor to prevent improper readings.
5. Measure, balance and if necessary match the wheel according to the instructions of the machine. Use the value for the first harmonic vibration. (18 lbs. maximum)
Tip: Do not use "Quick Match" mode; this mode does not measure road force. Also turn off "Smart Weight" balance feature, which can cause inaccurate readings.
6. Ensure that the wheel is centered and properly secured on the shaft of the balancer.
7. Follow all on-screen instructions to improve balance and reduce road force values (e.g. "Force Matching"). It is required to reduce road force to the lowest possible value on all tires with a maximum value of 18 lbs.
8. Visually check the rim runout. If any runout is suspected, remove the tire and check radial and lateral runout values using VAS 6230 or Hunter GSP9700 Tire Balancer.
Tip: Use adequate lubrication to ensure that tires are properly seated when they are installed on the wheel or are moved on a wheel to change mounting position. Be aware that excessive lubricant can cause a tire to slip on the wheel, which will have an impact on the balance and road force values. Please ensure that the road force values are printed out with the before and after values for each wheel and attach this documentation to the Repair Order.
9. If the original tires are installed on the vehicle and it is not possible to reduce the road force below 18 lbs. replace the affected tire with another tire of the same brand, size and load rating as the original.
Tip: A replacement is permitted only if the original tires are installed on the vehicle.
Tip: In case of high road force values in the replacement tire, it may be necessary to repeat steps 1 through 8.
10. Install the wheels according to instructions of the VAS 6230 according to the lowest vibration. The wheels/tire assembly with the lowest road force values should be installed closest to the driver. Keep in mind that directional tires may not allow every tire to be installed in its ideal position on the vehicle. See Repair Manual >> Running gear >> 44 wheels, tires, wheel alignment >> Installation of wheels/tires/tire pressure warning >> Instructions on wheel change/installation.
^ Lowest road force value - left front
^ Second lowest road force value - right front
^ Third lowest road force value - left rear
^ Highest road force value - right rear
11. Test drive vehicle and verify repair.
^ If the vibrations or steering wheel vibrations persist, proceed with TSB 2024687.