2008 MERCEDES-BENZ SL65AMG Owner's Manual

296 Operation
Tires and wheels
1Seating capacity information on the
Tire and Loading Information placardSteps for determining correct load limit
The following steps have been developed
as required of all manufacturers under Title
49, Code of U.S. Federal Regulations, Part
575 pursuant to the “National Traffic and
Motor Vehicle Safety Act of 1966”.
Step 1
Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kg or XXX lbs.” on
your vehicle’s Tire and Loading
Information placard.
Step 2
Determine the combined weight of the
driver and passengers that will be
riding in your vehicle.Step 3
Subtract the combined weight of the
driver and passengers from XXX kilo-
grams or XXX lbs.
Step 4
The resulting figure equals the avail-
able amount of cargo and luggage load
capacity. For example, if the “XXX”
amount equals 1 400 lbs. and there will
be five 150 lbs. passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs.
(1 400 - 750 (5 x 150) = 650 lbs.)
iData shown on Tire and Loading Information
placard example are for illustration purposes
only. Seating data are specific to each vehicle
and may vary from data shown in the illustration
below. Refer to Tire and Loading Information
placard on vehicle for actual data specific to your
vehicle.

297 Operation
Tires and wheels
Step 5
Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely
exceed the available cargo and luggage
load capacity calculated in step 4.
Step 6 (if applicable)
If your vehicle will be towing a trailer,
load from your trailer will be trans-
ferred to your vehicle. Consult this
manual to determine how this reduces
the available cargo and luggage load
capacity of your vehicle (
page 299).The following table shows examples on
how to calculate total and cargo load
capacities with varying seating configura-
tions and number and size of occupants.
The following examples use a load limit
of 1 500 lbs. This is for illustration
purposes only. Make sure you are
using the actual load limit for your vehicle
stated on the vehicle’s Tire and Loading
Information placard (
page 295).

298 Operation
Tires and wheels
The higher the weight of all occupants, the
less cargo and luggage load capacity is
available.
For more information, see “Trailer tongue
load” (
page 299).
ExampleCombined weight limit of
occupants and cargo
from Tire and Loading
Information placardNumber of
occupants
(driver and
passengers)Occupants weight Combined
weight of all
occupantsAvailable cargo/luggage and trailer
tongue weight (total load limit from
Tire and Loading Information
placard minus combined weight of
all occupants)
11 500 lbs1Occupant 1: 175 lbs175 lbs1 500 lbs - 175 lbs = 1 325 lbs
21 500 lbs2Occupant 1: 175 lbs
Occupant 2: 195 lbs370 lbs1 500 lbs - 370 lbs = 1 130 lbs

299 Operation
Tires and wheels
Certification label
Even after careful determination of the
combined weight of all occupants, cargo
and the trailer tongue load (if applicable)
(
page 299) as to not exceed the permis-
sible load limit, you must make sure that
your vehicle never exceeds the Gross Vehi-
cle Weight Rating (GVWR) and the Gross
Axle Weight Rating (GAWR) for either the
front or rear axle. You can obtain the
GVWR and GAWR from the certification
label. The certification label can be found
on the driver’s door B-pillar, see “Technical
data” (
page 444).Gross Vehicle Weight Rating (GVWR): The
total weight of the vehicle, all occupants,
all cargo, and the trailer tongue load
(
page 299) must never exceed the
GVWR.
Gross Axle Weight Rating (GAWR): The to-
tal allowable weight that can be carried by
a single axle (front or rear).
To assure that your vehicle does not ex-
ceed the maximum permissible weight
limits (GVWR and GAWR for front and rear
axle), have the loaded vehicle (including
driver, passengers and all cargo and, if ap-
plicable, trailer fully loaded) weighed on a
suitable commercial scale.Trailer tongue load
The tongue load of any trailer is an impor-
tant weight to measure because it affects
the load you can carry in your vehicle. If a
trailer is towed, the tongue load must be
added to the weight of all occupants riding
and any cargo you are carrying in the
vehicle. The tongue load typically is
10 percent of the trailer weight and every-
thing loaded in it.
Your Mercedes-Benz has been designed
primarily to carry passengers and their
cargo. Mercedes-Benz does not recom-
mend trailer towing with your vehicle.

300 Operation
Tires and wheels
Recommended tire inflation pressure
Your vehicle is equipped with the Tire and
Loading Information placard located on
the driver’s door B-pillar (
page 294).
The tire inflation pressure should be
checked regularly and should only be ad-
justed on cold tires. The tires can be con-
sidered cold if the vehicle has been parked
for at least 3 hours or driven less than
1 mile (1.6 km). Follow recommended cold tire inflation
pressures listed on the Tire and Loading
Information placard on the driver’s door
B-pillar.
Keeping the tires properly inflated
provides the best handling, tread life and
riding comfort.
In addition to the Tire and Loading
Information placard on the driver’s door
B-pillar, also consult the tire inflation
pressure label (if available) on the fuel filler
flap (page 279) for any additional infor-
mation pertaining to special driving situa-
tions. For more information, see
“Important notes on tire inflation
pressure” (
page 301).
Warning!G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.
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.

301 Operation
Tires and wheels
1Tire and Loading Information placard
with recommended cold tire inflation
pressures
The Tire and Loading Information placard
lists the recommended cold tire inflation
pressures for maximum loaded vehicle
weight. The tire inflation pressures listed
apply to the tires installed as original
equipment.Important notes on tire inflation
pressure
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.
If you will be driving your vehicle at high
speeds of 100 mph (160 km/h) or higher,
where it is legal and conditions allow,
consult the tire inflation pressure label (if
available) on the inside of the fuel filler flap
on how to adjust the cold tire inflation
pressure. If you do not adjust the tire infla-
tion pressure, excessive heat can build up
and result in sudden tire failure.Be sure to readjust the tire inflation
pressure for normal driving speeds. You
should wait until the tires are cold before
adjusting the tire inflation pressure.
Some vehicles may have supplemental tire
inflation pressure information for vehicle
loads less than the maximum loaded vehi-
cle condition. If such information is provid-
ed, it can be found on the tire inflation
pressure label located on the inside of the
fuel filler flap (
page 279).
Tire inflation pressure changes by approxi-
mately 1.5 psi (0.1 bar) per 18°F (10°C) of
air temperature change. Keep this in mind
when checking tire inflation pressure
where the temperature is different from
the outside temperature.
iData shown on Tire and Loading Information
placard example are for illustration purposes
only. Tire data are specific to each vehicle and
may vary from data shown in the illustration
below. Refer to Tire and Loading Information
placard on vehicle for actual data specific to your
vehicle.
Warning!G
If the tire inflation pressure drops
repeatedly:

Check the tires for punctures from
foreign objects.

Check to see whether air is leaking from
the valves or from around the rim.
iDriving comfort may be reduced when the
tire inflation pressure is adjusted to the value for
speeds above 100 mph (160 km/h) as specified
on the tire inflation pressure label located on the
inside of the fuel filler flap.

302 Operation
Tires and wheels
Checking tire inflation pressure
Regularly check your tire inflation pressure
at least once a month.
Check and adjust the tire inflation
pressure when the tires are cold. The tires
can be considered cold if the vehicle has
been parked for at least 3 hours or driven
less than 1 mile (1.6 km).
If you check the tire inflation pressure
when the tires are warm (the vehicle has
been driven for several miles or sitting less
than 3 hours), the reading will be
approximately 4 psi (0.3 bar) higher than
the cold reading. This is normal. Do not let
air out to match the specified cold tire in-
flation pressure. Otherwise, the tire will be
underinflated.Checking tire inflation pressure
manually
Follow the steps below to achieve correct
tire inflation pressure:
Remove the cap from the valve on one
tire.
Firmly press a tire gauge onto the
valve.
Read tire inflation pressure on tire
gauge and check against the recom-
mended tire inflation pressure on the
Tire and Loading Information placard
on the driver’s door B-pillar
(
page 294) or, if available, the tire
inflation pressure label on the inside
of the fuel filler flap. If necessary, add
air to achieve the recommended tire
inflation pressure.
Warning!G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.
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.

303 Operation
Tires and wheels
Install the valve cap.
Repeat this procedure for each tire.Run Flat Indicator (Canada only)
While the vehicle is being driven, the Run
Flat Indicator monitors the set tire inflation
pressures by evaluating each wheel’s rota-
tional speed. This allows the system to de-
tect a significant loss of pressure in a tire.
If a wheel’s rotational speed changes due
to falling tire inflation pressure, you will
see a corresponding warning message in
the multifunction display.
The Run Flat Indicator may function in a re-
stricted manner or with a delay

if snow chains are mounted to the
vehicle

in presence of ice and snow

if you are driving on a loose surface
(e.g. sand or gravel)

if you are driving in a very sporty man-
ner (involving rapid acceleration or high
speeds in curves)
iIf you have overfilled the tire, release tire in-
flation pressure by pushing the metal stem of the
valve with e.g. a tip of a pen. Then recheck the
tire inflation pressure with the tire gauge.Warning!G
When the multifunction display shows the
message
Tire Pressure Check Tires,
one or more of your tires is significantly un-
derinflated. You should stop and check your
tires as soon as possible, and inflate them to
the proper tire inflation pressure as indicat-
ed on the vehicle’s Tire and Loading
Information placard or, if available, on the
tire inflation pressure label. Driving on a sig-
nificantly under-inflated tire causes the tire
to overheat and can lead to tire failure. Un-
derinflation also reduces fuel efficiency and
tire tread life, and may affect the vehicle’s
handling and stopping ability. Each tire, in-
cluding the spare, should be checked
monthly when cold and set to the recom-
mended tire inflation pressure as specified
on the Tire and Loading Information placard
on the driver’s door B-pillar (
page 295) or,
if available, on the tire inflation pressure la-
bel located on the inside of the fuel filler flap
(
page 279).