2005 MERCEDES-BENZ G55AMG fuel pressure

268 OperationTires and wheelsMaximum tire inflation pressure
1Maximum permissible tire inflation
pressure
This is the maximum permissible tire
inflation pressure for the tire.Always follow the recommended tire
inflation pressure (
page 257) for proper
tire inflation.Uniform Tire Quality Grading Standards
(U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistance
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.
Warning!
G
Never exceed the max. tire inflation
pressure. Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and / or unevenly, adverse-
ly affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride com-
fort, wear unevenly, increase stopping dis-
tance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road de-
bris, potholes etc.
iFor illustration purposes only. Actual
data on tires are specific to each vehi-
cle and may vary from data shown in
above illustration.

271 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.
GTW (G
ross T
railer W
eight)
The GTW is the weight of the trailer plus
the weight of all cargo, equipment, luggage
etc. loaded on the trailer.

272 OperationTires and wheelsGVW (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.
GVWR (G
ross V
ehicle W
eight R
ating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passen-
gers, fuel, and cargo and, if applicable,
trailer tongue load). It is indicated on
Certification label located on the driver’s
door B-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to one psi; another metric unit for
air pressure is bars. There are
100 kilopascals (kPa) to one bar.Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
vehicle capacity weight and production
options weight.
Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, heavy duty battery,
and special trim.
PSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure
listed on placard located on driver’s door
B-pillar for normal driving conditions.
Provides best handling, tread life and
riding comfort.

292 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
?
(USA only)
±
(Canada only)
The yellow engine mal-
function indicator lamp
comes on while driving.
There is a malfunction of:

The fuel management system


The ignition system


The emission control system


Systems which impact emissions
Such malfunctions may result in excessive
emissions values and may switch the engine
to its limp-home mode. Serious damage can
occur to the emission system.

Have the vehicle checked as soon as possi-
ble by an authorized Mercedes-Benz Light
Truck Center.
An on-board diagnostic connector is used
by the service station to link the vehicle to
the shop diagnostics system. It allows the
accurate identification of system malfunc-
tions through the readout of diagnostic trou-
ble codes. It is located near the hood lock
release on the upper left of footwell.
A loss of pressure has been detected in the
fuel system. The fuel cap may not be closed
properly or the fuel system may be leaky.

Check the fuel cap (
page 235).
If it is not closed properly:

Close the fuel cap.
If it is closed properly:

Have the fuel system checked by an autho-
rized Mercedes-Benz Light Truck Center.
Your fuel tank is empty.

After refueling start, turn off and restart the
engine three or four times in succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.

311 Practical hints
What to do if …
Display symbol
Display message
Possible cause
Possible solution
A
RESERVE FUEL
GO TO GAS STATION
The fuel level has dropped below the re-
serve mark.

Refuel at the next gas station
(page 235).
CHECK GAS CAP
SEE OPERATOR’S MANUAL
A loss of pressure has been detected in
the fuel system. The fuel cap may not be
closed properly or the fuel system may be
leaky.

Check the fuel cap (
page 235).
If it is not closed properly:

Close the fuel cap.
If it is closed properly:

Have the fuel system checked by an
authorized Mercedes-Benz Light Truck
Center.
Y
HOOD OPEN!
You are driving with the hood open.

Close the hood (
page 239).
I
REMOVE KEY!
You have forgotten to remove the
SmartKey.

Remove the SmartKey from the starter
switch.
REPLACE KEY
DRIVE TO WORKSHOP!
No additional code available for
SmartKey.

Visit an authorized Mercedes-Benz
Light Truck Center.

350 Practical hintsFlat tireLowering the vehicle
Using the pump lever, open the lower-
ing screw on the jack approximately
one turn (
page 348).
The vehicle is resting fully on its own
weight.

Remove the jack.
After use, disassemble pump handle
(page 348) and store jack in the des-
ignated storage compartment
(page 322).
1-5 Wheel bolts

Tighten the five wheel bolts evenly, fol-
lowing the diagonal sequence illustrat-
ed (1 to 5), until all bolts are tight.
Observe a tightening torque of 97 lb-ft
(130 Nm).

Press the jack piston in again and close
the lowering screw. Store the jack
(page 322) and the other vehicle
tools (
page 321).

After changing the wheel, secure the
damaged wheel on the spare wheel
mounting bracket (
page 324). Make
sure the wheel cannot come loose.

Check the tire inflation pressure and
correct it if necessary.
A table with the tire pressure values for
your vehicle is located on the fuel filler
flap.
Warning!
G
Have the tightening torque checked after
changing a wheel as soon as possible. The
wheels could come loose if they are not
tightened to a torque of 97 lb-ft (130 Nm).

369 Technical data
Rims and tires
Rims and tires
Use only tires and rims which have been
specifically developed for your vehicle and
tested and approved by Mercedes-Benz.
Other tires and rims can have detrimental
effects, such as:

Poor handling characteristics


Increased noise


Increased fuel consumption
!Moreover, tires and rims not approved
by Mercedes-Benz may, under load,
exhibit dimensional variations and dif-
ferent tire deformation characteristics
that could cause them to come into
contact with the vehicle body or axle
parts. Damage to the tires or the vehi-
cle may be the result.
iFurther information on tires and rims is
available at any authorized
Mercedes-Benz Light Truck Center.
A placard with the recommended tire
inflation pressures is located on the
driver’s door B-pillar. Some vehicles
may have supplemental tire inflation
pressure information for driving at high
speeds (
page 258) or for vehicle
loads less than the maximum loaded
vehicle condition. If such information is
provided, it can be found on the placard
located on the inside of the fuel filler
flap. The tire inflation pressure should
be checked regularly and should only
be adjusted on cold tires. Follow tire
manufacturer’s maintenance recom-
mendation included with vehicle.

377 Technical data
Fuels, coolants, lubricants, etc.
Fuel requirements
Only use premium unleaded fuel:

The octane number (posted at the
pump) must be 91 min. It is an average
of both the Research (R) octane num-
ber and the Motor (M) octane number:
(R+M) / 2). This is also known as the
ANTI-KNOCK INDEX.
Unleaded gasoline containing oxygenates
such as ethanol, IPA, IBA and TBA can be
used provided the ratio of any one of these
oxygenates to gasoline does not exceed
10%; MTBE must not exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using mixtures of ethanol and methanol is
not allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build-up of carbon
deposits.
After an extended period of using fuels
without such additives, carbon deposits
can build up especially on the intake valves
and in the combustion area, leading to
engine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking/pinging


Misfire


Power lossIn areas where carbon deposits may be en-
countered due to lack of availability of gas-
olines which contain these additives,
Mercedes-Benz recommends the use of
additives approved by us for use on
Mercedes-Benz vehicles. Refer to Factory
Approved Service Products pamphlet for
a listing of approved product(s). Follow
directions on product label.
Do not blend other specific fuel additives
with fuel. This only results in unnecessary
cost and may be harmful to the engine
operation.
Damage or malfunction resulting from
poor fuel quality or from blending addition-
al fuel additives other than those tested
and approved by us for use on
Mercedes-Benz vehicles listed in the
Factory Approved Service Products
pamphlet are not covered by the
Mercedes-Benz Limited Warranty.