Volkswagen ID.3: Wheels, tyres. axle align. Handling problems

Volkswagen ID.3 (E11, E12) 2020-2024 Service Manual / Running gear / Wheels and Tyres Guide – General Information / Wheels, tyres. axle align. Handling problems

General notes on tyre noise
Flat spots (from locking wheels)
General information
Conicity
Remedies when vehicle pulls to one side
Strategic rotation of wheels for non-directional tyres
Strategic rotation of wheels having unidirectional tyres
Vibration, causes for vibration
Vibration, conducting a road test before balancing wheels
Vibration, vibration control system
Eliminating flat spots caused by storage or handling

General notes on tyre noise

Tyre noise that can be heard by the human ear is caused by vibrations which are transmitted by the air from the source of the sound to our ears.

Of interest here are the noises caused by certain characteristics and effects while the tyres are rolling (source of the sound).

The cause of the noise is largely dependent on the combination of the road surface and tyres.

The structure and material of the road surface will greatly affect tyre noise. For example, the noise level on a wet road is much higher than on a dry road.

The pattern of the tyre tread also has a significant influence on tyre noise. Tyres with transverse grooves at a 90° angle generate more noise than tyres with grooves running diagonally.

Small tread blocks are unstable. Their highly pronounced deformation agitates the air as the tyres roll. This creates the air vibrations that cause tyre noise.

Wider tyres are louder. They need more tread channels to displace water. When they are rolling, these tread channels displace the air, also creating air vibrations.

Further effects that also influence tyre noise:

♦ “Tyre vibration” is the principal cause of tyre noise. It is caused by the columns of air in the tread channels being agitated.

♦ “Air pumping” is the compression and expansion of the air caused by the deformation of the tread blocks as the tyre contact patch moves along the road surface.

Useful information regarding tyre noise

Tyre noise is determined primarily by the tyres and the road surface.

The coarseness, structure and material of the road surface influence tyre noise.

The widths of the tyre and the rim, among other things, influence tyre noise. Due to their larger contact area, wider tyres will cause more tyre noise than narrow tyres, as more air has to be displaced and more “mass” is agitated to create vibrations.

A wider wheel rim will also cause a tyre to have a wider contact patch. The effect on tyre noise is thus very similar to that of a wider tyre. Moreover, the damping characteristics of the tyre may also be adversely affected by the wider wheel rim.

On vehicles with a front-mounted engine, tyre noise is more perceptible at the rear of the vehicle, as wind and engine noises are not as loud there.

Flat spots (from locking wheels)

Flat spots can result from an extreme brake application which causes the wheels to lock, so that the rubber is worn off at the contact patch between the tread and the road surface.

As the tyres slide over the road surface, friction generates heat, which also reduces the wear resistance of the tread material.

Not even a highly wear-resistant tread compound can prevent the flat spots caused by violent braking.

Even ABS-controlled brake systems cannot prevent brief locking of the wheels, and thus, minor flat spots.

The degree of such wear depends largely on the vehicle speed, the road surface and the load placed on the wheel. The following examples should make this clear.

If a vehicle is braked to a standstill on a dry surface with the wheels locked, the amount of rubber worn from the tyre will cover an area the size of a postcard and will have a thickness of:

♦ up to 2.0 mm when braking from a speed of 57 km/h (23.8 m braking distance)

♦ up to 3.3 mm when braking from a speed of 75 km/h (41.8 m braking distance)

♦ up to 4.8 mm when braking from a speed of 92 km/h (71.6 m braking distance)

Flat spots in tread

Tyres with such damage must no longer be used and must be renewed.

General information

Perform a road test to determine whether a vehicle is pulling to one side and if so, which side. If the vehicle pulls to one side → Chapter.

When wheel alignment is checked, include the wheel alignment test results in tyre complaint report.

Manufacturer's tolerances can lead to a slight amount of taper (asymmetry) in the tyre carcass. The rolling tyre then develops a lateral force which acts directly on the wheel suspension, leading to self-steering of the vehicle. Strategic rotation of the wheels can balance out this self-steering behaviour.

Conicity

Conicity is caused by a slight offset of the tread and/or the belt (amounting to a few tenths of a millimetre) relative to the geometric centre of the tyre. Taper is not visible and cannot be measured with equipment available in the workshop.

Parts of a tyre

1 - Bead

2 - Shoulder

3 - Tread

4 - Steel cord belt

A - Geometrical centre of tyre

B - Actual centre of belt. It can be offset to inside or outside.

Exaggerated for clarity.

1 - Offset of belt and tread

F1 - Unequal vertical wheel forces

F2 - Unequal vertical wheel forces

Fk - Conicity force

The offset produces differences in stiffness at the inner and outer shoulders of the tyre, resulting in differing vertical wheel forces. Consequently the belt or tread will not be pressed onto the road surface with the same force (F1, F2). A conical, or tapered, shape develops. The resulting force (conicity force Fk) can, depending on the speed, become so great that the vehicle then pulls to one side.

If the force Fk on one wheel of the axle is, for example, 50 Newton, and also 50 Newton on the other wheel, and both forces are exerted in the same direction, the forces are cumulated. Reversing a tyre on the rim can compensate for the lateral pull because the forces then act in opposite directions.

Because the direction in which the force of taper is exerted is not visible, only road tests and strategic rotation of wheels and tyres can establish which tyres cause the pulling.

The tyre consists of numerous components and materials which are vulcanised to form a single part at the end of a complicated manufacturing process. The result is differing production tolerances which make themselves noticeable through more or less strong lateral forces (conicity forces). These forces can also occur in new tyres.

Pulling to one side on front axle

Pulling to one side can be caused by the running gear. However, experience shows that in 90 % of all complaints, the tyres cause pulling to one side.

Pulling to one side during normal driving

On a straight, level road surface, the vehicle wants to pull to one side at a constant speed or with moderate acceleration. Force can be felt at the steering wheel.

Pulling to one side during fast acceleration

Pulling to one side during fast acceleration is, in part, due to the basic design of vehicles with front wheel drive. Different friction levels at the left and right wheels or possible irregularities in the road surface (potholes) and consequently varying road adhesion have a substantial influence on the handling characteristics. This does not constitute a complaint which is covered by the warranty.

Remedies when vehicle pulls to one side

Test conditions before and during the road test:

– Check all suspension components on the front and rear axles for damage.

– Check tyre pressure and correct if necessary.

– Check the tyres for external damage. Punctures, cuts, bubbles on the sidewalls, flat spots from braking and/or damage to the tread.

– Ask the customer if the tyre had been damaged by a nail or similar object and was repaired by a tyre dealer. It may be necessary to renew such tyres.

– Check tyres for even wear and tread depth.

– Are all tyres of the same type, manufacture and tread pattern?

– If the tyres are non-directional, ensure that all DOT classifications on the tyre face outwards. The wheels and/or tyres on the vehicle may have already been changed around at an earlier date.

– Is the make of tyre approved by the factory as original equipment?

– Perform the road test on a road that is straight and even, has no "tram lines" (indents from heavy traffic) or adverse camber.

– Perform the road test with the customer under the conditions specified above. Ask the customer to demonstrate the problem.

Note

There must be no cross wind during the road test.

If the complaint is justified, we recommend rotating the wheels and tyres as described below.

Before starting work, make sure to observe the following:

Note

♦ Mark the tyres before the first rotation, e.g. FL, FR, RL, RR.

♦ After rotating wheels or reversing the tyre on its rim, you must observe very carefully how the vehicle behaves during the road test. Note how and what was changed.

♦ Assess the intensity of or a possible change in the tendency to pull to one side.

♦ For this purpose, it is important that the road tests are always performed by the same person on the same road. It is best to drive the “test course” in both directions.

♦ Replacing a tyre with a new tyre does not guarantee that pulling to one side will be eliminated. Therefore it is recommended as a first step to carry out the strategic rotation of the wheels as described below.

♦ If there are large differences in the tread depth of the tyres on the front and rear axles, the tyres with the deeper tread should always be mounted on the rear axle.

Strategic rotation of wheels for non-directional tyres

Strategic rotation of wheels for non-directional tyres↓Perform a road test to determine if the vehicle pulls to one side and if so, which side.↓If the vehicle pulls to one side, interchange the front wheels.↓Carrying out road testVehicle travels in a straight line - ENDVehicle pulls to other sideVehicle pulls to the same side↓↓Reverse one front tyre on its rim (direction of rotation is reversed).Interchange front and rear tyres.↓↓Carrying out road testCarrying out road testVehicle travels in a straight line - ENDVehicle travels in a straight line - ENDVehicle does not travel in a straight line.Vehicle does not travel in a straight line.↓↓Interchange the front and rear wheels.Vehicle pulls to other sideNo change↓↓↓Carrying out road testReverse one front tyre on its rim (direction of rotation is reversed)Check alignment of front and rear wheels and adjust if necessary.Vehicle travels in a straight line - END If the alignment is correct, contact Product Support.Vehicle does not travel in a straight line. ↓ Interchange front wheels. ↓↓ Carrying out road testCarrying out road test Vehicle travels in a straight line - ENDVehicle does not travel in a straight line.Vehicle travels in a straight line - END ↓Vehicle does not travel in a straight line. Mount new tyres on front axleMount new tyres on front axle ↓↓ Carrying out road testCarrying out road test Vehicle travels in a straight line - ENDVehicle travels in a straight line - END ↓↓ Vehicle does not travel in a straight line; contact Product Support.

Strategic rotation of wheels having unidirectional tyres

Strategic rotation of wheels having unidirectional tyres↓Perform a road test to determine if the vehicle pulls to one side and if so, which side.↓If the vehicle pulls to one side, interchange front and back wheels with tyres.↓Carrying out road testVehicle travels in a straight line - ENDVehicle does not travel in a straight line.↓First renew one tyre on the front axle.↓Carrying out road testVehicle travels in a straight line - ENDVehicle does not travel in a straight line.↓Renew other tyre on the front axle.↓Carrying out road testVehicle travels in a straight line - ENDVehicle does not travel in a straight line.↓Check front and rear wheel alignment.↓Carrying out road testVehicle travels in a straight line - ENDVehicle does not travel in a straight line; contact Product Support.

Vibration, causes for vibration

Rough running can have a number of different causes. It can also be caused by tyre wear. Tyre wear caused by driving is not always evenly spread across the entire running surface of the tyre. This causes slight imbalances which affect the smooth running of a wheel which was previously exactly balanced.

Minor imbalances will not be felt at the steering wheel, but that does not mean that they are not there. They increase wear on the tyre and thus reduce the tyre service life.

Recommendation

To ensure

● optimal safety,

● smoothest possible running and

● even wear

Throughout a tyre's service life, we recommend having the wheels and tyres balanced at least twice during the tyre's service life.

Vibration, conducting a road test before balancing wheels

If a customer brings a vehicle to the workshop complaining about “vibration”, a road test is essential prior to balancing the wheels.

♦ This will give you information about the nature of the rough running.

♦ You will be able to determine the speed range in which rough running occurs.

– Raise the vehicle on a lifting platform immediately after the road test.

– Mark installation position on tyre.

Tyre positionMarked with …Front left tyreFLFront right tyreFRRear left tyreRLRear right tyreRR

– Remove wheels.

– Balance wheels.

Vibration, vibration control system

Using the vibration control system -VAS 6230 A- you can perform more functions than just stationary balancing.

A special feature of this system is the testing of the radial force of the wheel and tyre while rolling.

A roller presses against the wheel with a force of about 635 kg. This simulates the vertical tyre force against the road surface during travel.

Radial and lateral runout in the wheel and tyre and differences in the stiffness of the tyre cause the vertical force of the wheel to vary.

The -VAS 6230 A- detects and stores the position of the maximum measured radial force in the tyre. Then the position of the smallest distance between the wheel rim flange and the centre of the rim is measured.