Tire size designation, load-bearing capacity and speed rating
1 Tire width
2 Nominal aspect ratio in %
3 Tire code
4 Rim diameter
5 Load bearing index
6 Speed rating
Tire data is vehicle-specific and may deviate from the data in the example.
General: depending on the manufacturer's standards, the size imprinted in the tire wall may not contain any letters or may contain one letter that precedes the size description.
If there is no letter preceding the size description (as shown above): these are passenger vehicle tires according to European manufacturing standards.
If "P" precedes the size description: these are passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these are light truck tires according to U.S.
manufacturing standards.
If "T" precedes the size description: these are compact emergency spare wheels at high tire pressure, to be used only temporarily in an emergency.
Tire width: tire width 1 shows the nominal tire width in millimeters.
Nominal aspect ratio: aspect ratio 2 is the size ratio between the tire height and the tire width and is shown in percent. The aspect ratio is calculated by dividing the tire width by the tire height.
Tire code: tire code 3 specifies the tire type.
"R" represents radial tires. "D" represents diagonal tires, "B" represents diagonal radial tires.
Optionally, tires with a maximum speed of over 149 mph(240 km/h) may have "ZR" in the size description depending on the manufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter 4 is the diameter of the bead seat, not the diameter of the rim flange. The rim diameter is specified in inches (in).
Load bearing index: load bearing index 5 is a numerical code which specifies the maximum load-bearing capacity of a tire.
WARNING
The tire load rating must always be at least
half of the GAWR of your vehicle. Otherwise,
sudden tire failure may be the result which
could cause an accident and/or serious injury
to you or others.
Always replace rims and tires with rims and
tires having the same specifications
(designation, manufacturer and type) as
shown on the original part.
WARNING
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Example:
The load bearing index 91 is equivalent to a
maximum load of 1356 lbs (615 kg) that the
tire can carry. For further information on the
maximum tire load in kilograms and pounds.
For further information on the load bearing index, see Load index.
Speed rating: speed rating 6 specifies the approved maximum speed of the tire.
WARNING
Even when permitted by law, never operate a
vehicle at speeds greater than the maximum
speed rating of the tires.
Exceeding the maximum speed for which tires
are rated can lead to sudden tire failure,
causing loss of vehicle control and possibly
resulting in an accident and/or serious
personal injury and possible death, for you
and for others.
Regardless of the speed rating always observe the speed limits. Drive carefully and adapt your driving style to the traffic conditions.
See also:
Towing a vehicle with both axles on the ground
When having your vehicle towed, observe the
important safety notes.
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Correct use of the seat belts
WARNING
USE SEAT BELTS PROPERLY
• Seat belts can only work when used
properly. Never wear seat belts in any other
way than as described in this section, as
that could result in seriou ...
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Different temperatures can be set for the driver's and front-passenger sides.
Turn the SmartKey to position 2 in the ignition lock.
To increase/reduce: turn controls 1 and 8 clockwise or cou ...