message will appear in the multifunction
display.GWarning!
When the multifunction display shows the
message  Tire Pressure Check Tires , one
or more of your tires are significantly
underinflated. You should stop and check
your tires as soon as possible, and inflate
them to the proper tire inflation pressure as
indicated on the vehicle’s Tire and Loading
Information placard or on the tire inflation
pressure label.
Driving on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure. Underinflation also reduces fuel
efficiency and tire tread life, and may affect
the vehicle’s handling and stopping ability.
Each tire, including the spare, should be
checked at least once a month when cold.
Inflate the tires to the recommended tire
inflation pressure as specified on
R the Tire and Loading Information placard on
the driver’s door B-pillar
or
R the tire inflation pressure label located on
the inside of the fuel filler flap
GWarning!
The tire pressure loss warning system does
not provide a warning for wrongly selected tire
inflation pressures. Always adjust tire
inflation pressure according to the Tire and
Loading Information placard on the driver's
door B-pillar or on the tire inflation pressure
label located on the inside of the fuel filler flap.
The tire pressure loss warning system does
not replace regular checks of the tire inflation
pressures since a gradual pressure loss in
more than one tire cannot be detected by the
tire pressure loss warning system.
The tire pressure loss warning system is not
able to issue a warning due to a sudden
dramatic loss of tire inflation pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by carefully
applying the brakes and avoiding abrupt
steering maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted on your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style
(cornering at high speeds or driving with
high rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy load or a load
on the roof.
Restarting the tire pressure loss
warning system
Restart the tire pressure loss warning system
if you have:
R changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
XBefore restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions,
using the Tire and Loading Information
placard on the B-pillar on the driver's side
or the tire pressure table on the fuel filler
flap.XObserve the notes in the section on tire
pressures ( Y page 336).GWarning!
The tire pressure loss warning system can
only give reliable warnings if you have set the
correct tire pressure.
If an incorrect tire pressure is set, these
incorrect values will be monitored.
A tire with insufficient pressure results in
vehicle instability when driving, thus
increasing the risk of an accident.
340Tire pressuresTires and wheels
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Tires of the same dimensions
i BA: Both axlesGL 350 BlueTEC
GL 450GL 550R19BAAlloy wheels
Offset8.5 J x 19 H2
2.20 in (56 mm)8.5 J x 19 H2
2.20 in (56 mm)All-weather 
tires 46,
 47275/55 R19 111 H M+S275/55 R19 111 H M+SWinter tires265/55 R19 109 H
M+S i 48265/55 R19 109 H
M+S iAll-terrain tires 46275/55 R19 111 H 
M+S48275/55 R19 111 H M+SGL 350 BlueTEC 49
GL 450GL 550R20BAAlloy wheels
Offset8.5 J x 20 H2
2.20 in (56 mm)8.5 J x 20 H2
2.20 in (56 mm)All-weather 
tires 46, 50275/50 R20 109 H M+S
MOExtended275/50 R20 109 H M+S
MOExtendedGL 350 BlueTEC
GL 450GL 550R21BA AMG alloy wheels
Offset—10 J x 21 H2
1.46 in (37 mm)All-weather tires 46—295/40 R21 111 V XL
M+S
Spare wheel
i Vehicles with MOExtended tires (tires with run-flat characteristics) are not equipped with
TIREFIT at the factory.
i The GL 350 BlueTEC is not equipped with an emergency spare wheel.
46
Use of snow chains not permitted.
47 GL 350 BlueTEC: Canada only.
48 GL 350 BlueTEC (USA only): standard tires without run-flat characteristics. Retrofitting a TIREFIT kit is
recommended.
49 USA only.
50 Tires with run-flat characteristics must only be used in conjunction with an activated tire pressure loss 
warning system or TPMS.Wheel/tire combinations359Tires and wheelsBA 164.8 USA, CA Edition B 2011; 1; 2, en-USd2sboikeVersion: 3.0.3.52010-04-21T15:08:44+02:00 - Seite 359Z 
iThe prescribed tire pressure is also given on a yellow label on the emergency spare wheel."Minispare" emergency spare wheel 51GL 450
GL 550R19Wheels
Offset4.5 B x 19 H2
1.58 in (40 mm)TiresT 165/90 D19 119 M
or
T 165/90 R19 119 MTire pressure420 kPa (4.2 bar/61 psi)51 Use of snow chains not permitted.360Wheel/tire combinationsTires and wheels
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