Rim diameter
The nominal diameter of the wheel's tire bead seating surface. If you change your wheel size, to wheels of a different diameter, you will have to purchase new tires to match the new wheels.
Rim size
Designation means rim diameter and width.
Rim type designation
The industry or manufacturer's designation for a rim by style or code.
Rim width
The nominal distance between wheel rim flanges.
Section width
The linear distance between the exteriors of the sidewalls of an inflated tire, excluding elevations due to labeling decoration, or protective bands.
Sidewall
The portion of a tire between the bead and the tread.
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
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 guaran-tee 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.
The Gross Axle Weight Rating (GAWR) is the maximum load that can be carried at each of the vehicle's 2 axles (by the front or rear tires). GVWR and GAWR are listed on the safety compliance label on the driver door jamb. Your vehicle has 5 total seating positions: 2 in the front and 3 in back. Each seating position has a safety belt. Because there is an upper limit to your vehicle's total weight (GVWR), the weight of whatever is being carried (including the weight of a trailer hitch and the tongue weight of the loaded trailer) is also limited. More passengers, or passengers who are heavier than the assumed 150 lbs (68 kg), mean that less weight can be carried as luggage or other cargo. The tire pressure label on your Volkswagen also lists the maximum combined weight of all of the occupants and luggage or other cargo that the vehicle can carry.
WARNING
Overloading a vehicle can cause loss of vehicle control, a crash or other accident, serious personal injury, and even death.
x Carrying more weight than your vehicle was designed to carry will prevent the vehicle from handling properly and increase the risk of the loss of vehicle control.
x The brakes on a vehicle that has been overloaded may not be able to stop the vehicle in a safe distance.
x Tires on a vehicle that has been overloaded can fail suddenly, including a blowout and sudden deflation, causing loss of control and a crash.
x Always make sure that the total load being transported - including the weight of a trailer hitch and the tongue weight of a loaded trailer - does not make the vehicle heavier than the vehicle's Gross Vehicle Weight Rating.
Determining the correct load limit