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Rim
This is the part of the wheel on which the tireis mounted.
GAWR (Gross Axle Weight Rating)
The GAWR is the maximum gross axle weightrating. The actual load on an axle must neverexceed the gross axle weight rating. The grossaxle weight rating can be found on the vehicleidentification plate on the B-pillar on the driv-er's side.
Speed rating
The speed rating is part of the tire identifica-tion. It specifies the speed range for which thetire is approved.
GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weightof the vehicle including fuel, tools, the sparewheel, accessories installed, occupants, lug-gage and the drawbar noseweight, if applica-ble. The gross vehicle weight must not exceedthe gross vehicle weight rating GVWR as speci-fied on the vehicle identification plate on theB-pillar on the driver's side.
GVWR (Gross Vehicle Weight Rating)
The GVWR is the maximum permissible grossweight of a fully loaded vehicle (the weight ofthe vehicle including all accessories, occu-pants, fuel, luggage and the drawbar nose-weight, if applicable). The gross vehicle weightrating is specified on the vehicle identificationplate on the B-pillar on the driver's side.
Maximum loaded vehicle weight
The maximum weight is the sum of:
Rthe curb weight of the vehicle
Rthe weight of the accessories
Rthe load limit
Rthe weight of the factory installed optionalequipment
Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa corre-sponds to 1 psi. Another unit for tire pressureis bar. 100 kilopascals (kPa) are the equivalentof 1 bar.
Load index
In addition to the load-bearing index, the loadindex may also be imprinted on the sidewall ofthe tire. This specifies the load-bearing capa-city more precisely.
Curb weight
The weight of a vehicle with standard equip-ment including the maximum capacity of fuel,oil and coolant. It also includes the air-condi-tioning system and optional equipment if theseare installed in the vehicle, but does notinclude passengers or luggage.
Maximum load rating
The maximum load rating is the maximum per-missible weight in kilograms or lbs for which atire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for onetire.
Maximum load on one tire
Maximum load on one tire. This is calculatedby dividing the maximum axle load of one axleby two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire widthin percent.
Tire pressure
This is pressure inside the tire applying an out-ward force to each square inch of the tire'ssurface. The tire pressure is specified inpounds per square inch (psi), in kilopascal(kPa) or in bar. The tire pressure should onlybe corrected when the tires are cold.
Cold tire pressure
The tires are cold:
Rif the vehicle has been parked with the tiresout of direct sunlight for at least three hoursand
Rif the vehicle has not been driven furtherthan 1 mile (1.6 km)
All about wheels and tires287
Wheels and tires
Z
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Tread
The part of the tire that comes into contactwith the road.
Bead
The tire bead ensures that the tire sitssecurely on the wheel. There are several steelwires in the bead to prevent the tire from com-ing loose from the wheel rim.
Sidewall
The part of the tire between the tread and thebead.
Weight of optional extras
The combined weight of those optional extrasthat weigh more than the replaced standardparts and more than 2.3 kg (5 lbs). Theseoptional extras, such as high-performancebrakes, level control, a roof rack or a high-per-formance battery, are not included in the curbweight and the weight of the accessories.
TIN (Tire Identification Number)
This is a unique identifier which can be usedby a tire manufacturer to identify tires, forexample for a product recall, and thus identifythe purchasers. The TIN is made up of themanufacturer's identity code, tire size, tiretype code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is acode that contains the maximum load bearingcapacity of a tire.
Traction
Traction is the result of friction between thetires and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are distrib-uted over the tire tread. If the tire tread is levelwith the bars, the wear limit of
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Clean the contact surfaces of the wheel andthe brake disc thoroughly every time a wheelis rotated. Check the tire pressure and, if nec-essary, restart the tire pressure loss warningsystem or the tire pressure monitor.
Direction of rotation
Tires with a specified direction of rotation haveadditional benefits, e.g. if there is a risk ofhydroplaning. These advantages can only begained if the tires are installed correspondingto the direction of rotation.
An arrow on the sidewall of the tire indicatesits correct direction of rotation.
Storing wheels
Store wheels that are not being used in a cool,dry and preferably dark place. Protect the tiresfrom oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle
XStop the vehicle on solid, non-slippery andlevel ground.
XApply the electric parking brake manually.
XBring the front wheels into the straight-ahead position.
XShift the transmission to position ].
XSwitch off the engine.
XVehicles without KEYLESS-GO:removethe SmartKey from the ignition lock.
XVehicles with KEYLESS-GO:open the driv-er's door.The vehicle electronics now have status0.This is the same as the SmartKey havingbeen removed.
XVehicles with KEYLESS-GO:remove theStart/Stop button from the ignition lock(Ypage 118).
XIf included in the vehicle equipment, removethe tire-change tool kit from the vehicle.
XSafeguard the vehicle against rolling away.
iDue to differences in vehicle equipment,not all vehicles are equipped with a tire-change tool kit. For information on which
tools are required to perform a wheelchange on your vehicle, consult an author-ized Mercedes-Benz Center.
Necessary tire-changing tools can include,for example:
RJack
RWheel chock
RLug wrench
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock,it can be found in the tire-change tool kit(Ypage 252).
The folding wheel chock is an additional safetymeasure to prevent the vehicle from rollingaway, for example when changing a wheel.
XFold both plates upwards C.
XFold out lower plate D.
XGuide the lugs on the lower plate fully intothe openings in base plate
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Raising the vehicle
GWARNING
If you do not position the jack correctly at
the appropriate jacking point of the vehicle,
the jack could tip over with the vehicle
raised. There is a risk of injury.
Only position the jack at the appropriate
jacking point of the vehicle. The base of the
jack must be positioned vertically, directly
under the jacking point of the vehicle.
!Only position the jack at the appropriatejacking point of the vehicle. Otherwise, youcould damage the vehicle.
Observe the following when raising the vehi-cle:
RTo raise the vehicle, only use the vehicle-specific jack that has been tested andapproved by Mercedes-Benz. If used incor-rectly, the jack could tip over with the vehi-cle raised.
RThe jack is designed only to raise and holdthe vehicle for a short time while a wheelis being changed. It must not be used forperforming maintenance work under thevehicle.
RAvoid changing the wheel on uphill anddownhill slopes.
RBefore raising the vehicle, secure it fromrolling away by applying the parking brakeand inserting wheel chocks. Do not disen-gage the parking brake while the vehicle israised.
RThe jack must be placed on a firm, flat andnon-slip surface. On a loose surface, a large,flat, load-bearing underlay must be used. Ona slippery surface, a non-slip underlay mustbe used, e.g. rubber mats.
RDo not use wooden blocks or similar objectsas a jack underlay. Otherwise, the jack willnot be able to achieve its load-bearing capa-city due to the restricted height.
RMake sure that the distance between theunderside of the tires and the ground doesnot exceed 1.2 in (3 cm).
RNever place your hands and feet under theraised vehicle.
RDo not lie under the vehicle.
RDo not start the engine when the vehicle israised.
RDo not open or close a door or the trunk lidwhen the vehicle is raised.
RMake sure that no persons are present inthe vehicle when the vehicle is raised.
XUsing lug wrench C, loosen the bolts onthe wheel you wish to change by about onefull turn. Do not unscrew the bolts com-pletely.
The jacking points are located just behind thefront wheel housings and just in front of therear wheel housings (arrows).
Vehicles with AMG equipment:the vehiclehas covers installed to protect the vehiclebody next to the jacking points on the outersills.
290Changing a wheel
Wheels and tires
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