71 Safety and Security
Occupant safety
Warning!
G
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 sec-
tion, as that could result in serious inju-
ries in case of an accident.
Each occupant should wear his or her
seat belt at all times, because seat belts
help reduce the likelihood and potential
severity of injuries in accidents, includ-
ing rollovers. The integrated restraint
system includes SRS (driver air bag,
passenger air bag, kneebags,
head-thorax air bags) and ETD (seat belt
emergency tensioning device).
The system is designed to enhance the
protection offered to properly belted oc-
cupants in certain frontal (front air bags,
kneebags, and EDT) and side (head-tho-
rax air bags and EDT) impacts which ex-
ceed preset deployment thresholds.
Never wear the shoulder belt under your
arm, against your neck or off your shoul-
der. In a crash, your body would move
too far forward. That would increase the
chance of head and neck injuries. The
belt would also apply too much force to
the ribs or abdomen, which could se-
verely injure internal organs such as
your liver or spleen.
Never wear belts over rigid or breakable
objects in or on your clothing, such as
eyeglasses, pens, keys, etc., as these
might cause injuries.
Position the lap belt as low as possible
on your hips and not across the abdo-
men. If the belt is positioned across your
abdomen, it could cause serious injuries
in a crash.
Never use a seat belt for more than one
person at a time. Do not fasten a seat
belt around a person and another per-
son or other objects.
Belts should not be worn twisted. In a
crash, you wouldn’t have the full width
of the belt to manage impact forces. The
twisted belt against your body could
cause injuries.
Pregnant women should also use a
lap-shoulder belt. The lap belt portion
should be positioned as low as possible
on the hips to avoid any possible pres-
sure on the abdomen.
Never place your feet on the instrument
panel, dashboard or on the seat. Always
keep both feet on the floor in front of the
seat.
313 Operation
Tires and wheels
Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires:1Uniform Quality Grading Standards
(
page 320)
2DOT, Tire Identification Number (TIN)
(page 318)
3Maximum tire load (
page 319)
4Maximum tire inflation pressure
(
page 320)
5Manufacturer
6Tire ply material (
page 322)
7Tire size designation, load and speed
rating (
page 313)
8Load identification (
page 317)
9Tire nameTire size designation, load and speed
rating
1Tire width
2Aspect ratio in %
3Radial tire code
4Rim diameter
5Tire load rating
6Tire speed rating
iFor illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.
For more information, see “Rims and
tires” (
page 413).
iFor illustration purposes only. Actual
data on tires is specific to each vehicle
and may vary from data shown in above
illustration.
314 OperationTires and wheelsGeneral:
Depending on the design standards used,
the tire size molded into the sidewall may
have no letter or a letter preceding the tire
size designation.
No letter preceding the size designation
(as illustrated above): Passenger car tire
based on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only. Tire width
The tire width1 (
page 313) indicates
the nominal tire width in mm.
Aspect ratio
The aspect ratio2 (page 313) is the
dimensional relationship between tire
section height and section width and is
expressed in percentage. The aspect ratio
is arrived at by dividing section height by
section width.
Tire code
The tire code3 (
page 313) indicates
the tire construction type. The “R” stands
for radial tire type. Letter “D” means diag-
onal or bias ply construction; letter “B”
means belted-bias ply construction.
At the tire manufacturer’s option, any tire
with a speed capability above 149 mph
(240 km/h) can include a “ZR” in the size
designation (for example: 245/40 ZR 18).
For additional information, see “Tire speed
rating” (
page 315).Rim diameter
The rim diameter4 (
page 313) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Tire load rating
The tire load rating5 (page 313) is a
numerical code associated with the
maximum load a tire can support.
For example, a load rating of 91 corre-
sponds to a maximum load of 1 356 lbs
(615 kg) the tire is designed to support.
See also “Maximum tire load”
(
page 319) where the maximum load as-
sociated with the load index is indicated in
kilograms and lbs.
321 Operation
Tires and wheels
Quality grades can be found, where appli-
cable, on the tire sidewall between tread
shoulder and maximum section width. For
example:
All passenger car tires must conform to
federal safety requirements in addition to
these grades.Treadwear
The treadwear grade is a comparative rat-
ing based on the wear rate of the tire when
tested under controlled conditions on a
specified government test course. For ex-
ample, a tire graded 150 would wear one
and one-half (1
1/2) times as well on the
government course as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly
from the norm due to variations in driving
habits, service practices and differences in
road characteristics and climate.Traction
The traction grades, from highest to low-
est, are AA, A, B, and C. Those grades rep-
resent the tire’s ability to stop on wet
pavement as measured under controlled
conditions on specified government test
surfaces of asphalt and concrete. A tire
marked C may have poor traction perfor-
mance.
Treadwear
Traction
Temperature
200
AA
A
Warning!
G
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
323 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least three hours or
driven no more than one mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (G
ross V
ehicle W
eight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GWV must never exceed the
GWVR indicated on the certification label
located on the driver’s door B-pillar.
336 OperationVehicle carePaintwork, painted body components
Mercedes-Benz approved Paint Care
should be applied when water drops on the
paint surface do not “bead up”, normally
every three to five months, depending on
climate and washing detergent used.
Mercedes-Benz approved Paint Cleaner
should be applied if the paint surface
shows signs of embedded dirt (i.e. loss of
gloss).
Do not apply any of these products or wax
if your vehicle is parked in the sun or if the
hood is still hot.
Use the appropriate MB-Touch-Up Stick
for quick and provisional repairs of minor
paint damage (i.e. chips from stones, vehi-
cle doors, etc.).Engine cleaning
Prior to cleaning the engine compartment,
make sure to protect electrical compo-
nents and connectors from the intrusion of
water and cleaning agents.
Corrosion protection, such as
MB Anticorrosion Wax should be applied to
the engine compartment after every en-
gine cleaning. Before applying, all control
linkage bushings and joints should be lu-
bricated. The poly-V-belt and all pulleys
should be protected from any wax.Vehicle washing
Do not use hot water or wash your vehicle
in direct sunlight. Only use a mild car wash
detergent, such as Mercedes-Benz ap-
proved Car Shampoo.
Thoroughly spray the vehicle with a dif-
fused jet of water. Direct only a very weak
spray towards the ventilation intake. Use
plenty of water and rinse the sponge and
chamois frequently.
Rinse with clear water and thoroughly dry
with a chamois. Do not allow cleaning
agents to dry on the finish.
Due to the width of the vehicle, fold in ex-
terior rear view mirrors prior to running the
vehicle through an automatic car wash to
prevent damage to the mirrors.
420 Technical dataMain DimensionsModel
SLK 350
SLK 55 AMG
Overall vehicle length
160.7 in (4 082 mm)
160.9in (4087mm)
Overall vehicle width
70.4 in (1 788 mm)
70.6 in (1 794 mm)
Overall vehicle height
51.1 in (1 298 mm)
50.0 in (1 271 mm)
Wheelbase
95.7 in (2 430 mm)
95.7 in (2 430 mm)
Track, front
60.0 in (1526 mm)
60.0 in (1 524 mm)
Track, rear
61.0 in (1549 mm)
61.0 in (1 549 mm)