Information Regarding Tires
Information regarding tires
Identification markings on the tire sidewall
Example: Dunlop SP Sport 9000
1 - Size: 215/55 ZR16
2 - Manufacturer (trade name)
3 - Tread designation
4 - Code for tubeless tires
5 - Radial-ply tire construction (radially oriented fibres in body)
6 - Notes for versions with rim protection
7 - Date of manufacture - see tire aging Information About Tires
8 - E number = Approval number. Tire complies with European Guidelines ECE-R30 and EEC92/93
9 - Country of manufacture - Made in Germany.
10 - Internal DUNLOP tread code
11 - Department of Transportation (DOT)- the tire conforms to the U.S. Department of Transportation guidelines
12 - Example: Dunlop SP Sport 9000
DOT - Code ID number for manufacturers plant, tire size and tire model
13 - Maximum permissible load and maximum permissible inflation pressure information for North America
14 - Number of plies in the center of the tread and in the sidewalls and information about the material
15 - Position of TWIs (Tread Wear Indicators)
16 - Tread wear index - resistance to abrasion - based on US standard test
17 - Traction rating - evaluation of wet braking capacity A, B or C according to US test
18 - Temperature rating - evaluation of temperature rating A, B or C according to US test
19 - Safety notes for use or mounting of tire
20 - Reference to ultra lightweight tire construction, tires are up to 30% lighter
21 - Specified direction of rotation for tire
22 - In metro designation, required only for Brazil
Designations on sidewall of tires with run-flat system (PAX)
1. Tire width
2. Tire height to width ratio in %
3. Code for tire type R indicates radial
4. Rim diameter designation
5. Load rating code
6. Speed rating code
7. Winter tire/code for all-season tire
Speed rating / maximum speed
Load rating code / load index (LI)
The load rating can be found on the sidewall of the tire. It provides information about the maximum load that the tire can bear.
The load rating is included in the size designation of the tire (e.g. 195 R 15 91 H). It is indicated on the tire as a code according to ETRTO. The following table shows the load rating codes used at Audi with the corresponding load capacity of the tires.
Radial depressions
Radial depressions are slight concavities in the tire sidewall.
They run from the bead towards the shoulder of the tire.
Radial depressions are caused by the accumulation of material at the joints of the tire components.
Radial depressions do not influence:
^ Safety
^ Service life
^ Running characteristics or other properties of the tire.
Radial depressions are visible to varying extents. It is not necessary to inspect the tire or remove it from the rim.
What causes radial depressions?
Modern steel belted radial tires are constructed with single-ply sidewalls to save weight.
The sidewall components consist of long strips before they are joined together to form a tire. They must overlap at the joints. Consequently, slight unevenness or ripples are created in the area of the overlapping parts. The overlaps are easier to see from the outside due to the single-ply construction.
The valve
1. Valve body
2. Valve core
3. Valve cap
1. Valve body
The rubber valve for tubeless tires is designed to be an air-tight seal on the hole in the rim. The elastic material of the rubber valve body presses tightly into the hole in the rim.
In the case of valves with a threaded metal base, a rubber seal is used to seal the rim ' The lateral faces of the rim hole are sealing surfaces. They must be free of rust and dirt and must not be damaged.
2. Valve core
The valve core fills the most important task in the valve; it acts as a seal and enables you to adjust the inflation pressure. The small flat seal on the valve core can only function correctly if it is free of foreign particles, dirt and moisture.
3. Valve cap
A valve cap must always be screwed onto the valve. It prevents dirt from getting into the valve. Dirt in the valve could reach the seal on the valve plunger when the tire is inflated and lead to leakage.
The valve must be replaced every time a new tire is mounted.
If the vehicle is driven without caps on the valves, there is the danger that dirt may get into the valve. This leads to a gradual loss of air, which in turn can lead to the destruction of the tire.
Note:
^ The valve cap must be installed tightly to ensure air-tight sealing.
Tire storage
Storage area:
Rooms used for storing tires must be
^ Dark
^ Dry
^ Cool
^ Well ventilated
Stored tires must not come in contact with fuel, oil, grease or chemicals under any circumstances. Otherwise, the material in the tire will be damaged by chemical reactions which are not always visible.
As a result, dangerous situations can occur when the car is driven. However, tire damage occurs only if the tire is in contact with the chemical for a relatively long time. If a few drops of fuel drip onto the tire while you are filling the tank, this is of no concern.
Storing tires
Complete wheels
Tires mounted on wheels can be stored flat, stacked one on top of the other. The inflation pressure should be increased to a maximum of 3 bar.
Tires without wheels
Tires without wheels are best stored standing vertically. If tires are stacked for a long period of time, they will be pressed together quite considerably. They will then be more difficult to mount, as the tires do not sit on the bead seats. If tires are stored standing vertically, it is recommended to turn them every 14 days to avoid flat spots.
Tire aging
Tires age as a result of physical and chemical processes whereby the function can be impaired. Tires which are stored for long periods of time harden and become brittle faster than tires which are constantly in use on a vehicle. Older tires may develop hairline cracks as a result of aging. When tires are in regular use, the constant flexing activates softeners in the rubber, preventing hardening and the development of cracks.
It is important to not only take into account the tread depth, but also the age of spare tires, stored tires and tires which are not permanently in use. The tire age can be seen on the DOT designation, which includes the production date of the tire.
Example of a DOT number:
In this example, the production date is the 50th week of 2002 (the DOT number had 3 digits up to December 31, 1999).
Recommendation:
^ We recommend that you only use tires which are older than 6 years in emergencies and make sure you then drive with caution.
^ When new tires are mounted, the spare tire may also be used if it is in perfect condition and not more than 6 years old. The age of the tire has a great influence on the high-speed capability of the tire. It is possible to combine a spare tire which is several years old with new tires, however, this can have an adverse influence on car handling.
^ Tires are constantly being developed, which can lead, for example, to slight changes in the rubber compound, even if the tires are of the same make, size and tread pattern.
^ For safety reasons, tires of the same make and with the same tread pattern should be mounted on one axle. All Audi vehicles are factory-installed with four identical tires and wheels.
^ Vehicles with all wheel drive must always be equipped with four wheels with tires of the same size, construction, tread pattern and make.
Replacing tires
Tires must always be replaced when:
^ The legal minimum tread depth of 1.6 mm is reached,
^ There is visible mechanical damage
^ The tires are more than 6 years old.
Care and maintenance of alloy wheel rims
Regular care is required to maintain the decorative appearance of alloy wheels over a long period of time.
In particular road salt and dust from brake abrasion must be thoroughly washed off every 2 weeks; otherwise the finish of the alloy wheel will suffer.
Cleaning agents:
^ Plain water or water with soft soap
^ Water and essence of vinegar
^ Alloy wheel cleansers without acids or strong solvents
Do not exceed the soaking time of the cleaning agent.
The shorter the recommended soaking time, the stronger and more aggressive the cleaning agent.
If the finish is damaged, for example by stones, the damage must be repaired as quickly as possible.
Removing adhesive residue from glued balance weights on alloy rims:
^ Strong solvents and acids attack the finish on alloy wheels and the surface of the wheel becomes matt and milky. These substances should not be used.
^ To remove adhesive residue on alloy wheels, use alloy cleansers or a oil-based cleanser. Do not exceed the soaking time of the cleaning agent.
^ After cleaning or removing adhesive residue from wheels, rinse them with water.
Rotating wheels:
^ Vehicles with front-wheel drive exhibit more tread wear on the front wheels due to the greater forces they have to transmit.
^ In order for all 4 wheels on the vehicle to have the same service life, we recommend rotating the front and rear wheels/tires.
^ Make sure that uni-directional tires are not reversed.
^ The longer the tire runs at one position, the more it wears at certain points. It is advisable to rotate the wheels at short intervals, for example every 5,000 km.
^ Diagonal rotation is possible only with non-directional tires. This wheel rotation method is especially advantageous in the case of heel-and-toe wear.
^ If heel-and-toe wear has already progressed and the tread is worn to more than 50%, only slight improvements would be achieved and rotation is not recommended. The elasticity of the tread blocks declines and the heel-and-toe wear does not progress.