Sidewall separation
The parting of the rubber compound from the cord material in the sidewall.
Speed rating (letter code)
A standardized letter code indicating the maximum speed at which a tire is designed to be driven for extended periods of time. The ratings range from 93 mph or 150 km/h (“P”) to 186 mph or (300 km/h) “Y”.
The speed rating letter code, where applicable, is molded on the tire sidewall, Tire labeling. You may not find this information on all tires because it is not required by law.
Tire Pressure Monitoring System
A system that detects when at least one of a vehicle's tires is underinflated and illuminates a low tire-pressure warning light.
Tread
The portion of a tire that normally touches the road.
Tread rib
A tread section running circumferentially around a tire.
Tread separation
Tire failure caused by the tread pulling away from the tire carcass.
Tread wear indicators (TWI)
Raised areas within the main tread grooves that show, visually, when tires are worn and near the end of their useful life, Tread depth and tread wear indicators.
Uniform Tire Quality Grading (UTQG)
A tire information system developed by the U.S. National Highway Traffic Safety Administration (NHTSA) that is designed to help buyers compare tires. UTQG is not a safety rating, nor is it a guarantee that a tire will last for a certain number of miles or perform a certain way. It gives tire buyers more information to compare with factors such as price, brand loyalty and dealer recommendations. Under UTQG, tires are graded by the tire manufacturers in 3 areas: tread wear, traction and temperature resistance. UTQG information is molded into the tire sidewalls.
U.S. DOT Tire Identification Number (TIN)
A tire's serial number. It begins with the letters “DOT” (“Department of Transportation”) and indicates that the tire meets all federal standards. The next 2 numbers or letters indicate the plant where the tire was manufactured. The last 4 numbers represent the week and year of manufacture.
For example, the numbers 1709 mean that the tire was produced in the 17th week of 2009. Any other numbers are marketing codes used by the tire manufacturer. This information is used to help identify affected consumers if a tire defect requires a recall.
Vehicle capacity weight
The total rated cargo, luggage and passenger load. Passenger load is 150 lbs (68 kilograms) times the vehicle's total seating capacity (as listed on the label inside the driver door).
Vehicle maximum load on the tire
The load on an individual tire that is determined by taking each axle's share of the maximum loaded vehicle weight (GAWR) and dividing by 2.
Vehicle normal load on the tire
The load on an individual tire that is determined by taking each axle's share of the curb weight, accessory weight, and normal occupant weight (distributed according to the table below) and dividing by 2.
WARNING
Improper use of your vehicle jack can cause the vehicle to fall off the jack leading to serious personal injury. To help reduce the risk of serious personal injury:
x Use only jacks approved by Volkswagen for the vehicle. Other jacks might slip, even those approved for other Volkswagen models, but not for your vehicle.
x Always set up the jack on firm and level ground. The vehicle may slip off the jack if the jack is resting on soft or sloping ground. If necessary, place a sturdy board under the jack.
x On a hard, slippery surface (such as a tiled floor), use an anti-skid rubber mat or something similar to help prevent the jack from slipping.
x Position the jack only at the described vehicle lift points. Before you raise your vehicle, always make sure the jack claw properly grips the vertical rib under the sill so that the jack does not slip off when you are raising the vehicle .
x Never have any part of your body (such as your arm or leg) under the vehicle when it is supported by the jack. Never let other persons have any part of their body under the vehicle, either!
x If you must work under a vehicle raised on a floor jack, always make sure that the vehicle is safely supported on safety stands intended for that purpose that are strong enough to support the weight of the vehicle.
x Never lift the vehicle when it is tilted or inclined to one side or the engine is running.
x Never lift the vehicle when more than 1 tire is flat or damaged.
x Do not start the engine while the vehicle is supported by a jack. Engine vibrations may cause the vehicle to slip off the jack.
WARNING
Disregarding the safety-related checklist may lead to accidents and serious personal injuries.
x Always review and follow the checklist. Follow accepted safety practices and use common sense.
Changing a wheel
Fig. 171 Changing a wheel: Remove previously loosened wheel bolts using the screwdriver handle.
