oil pressure MERCEDES-BENZ R350 2008 W251 Owner's Manual

Page 8 of 569

Contents
Oxidation catalyst
(diesel engine).............................. 349
Emission control .......................... 350
Coolant temperature .................... 350
At the gas station .............................. 352
Refueling ...................................... 352
Check regularly and before a
long trip........................................ 354
Engine compartment ......................... 356
Hood ............................................ 356
Engine oil ..................................... 358
Transmission fluid level ................ 360
Coolant level ................................ 360
Windshield/rear window washer
system and headlamp cleaning
system* ....................................... 362
Tires and wheels ................................ 363
Important guidelines .................... 363
Tire care and maintenance........... 364
Direction of rotation ..................... 365
Loading the vehicle ...................... 366
Recommended tire inflation
pressure ....................................... 371
Checking tire inflation pressure ... 373
Tire labeling.................................. 384
Load identification ....................... 388DOT, Tire Identification Number
(TIN) .............................................. 388
Maximum tire load ........................ 390
Maximum tire inflation pressure ... 390
Uniform Tire Quality Grading
Standards (U.S. vehicles) .............. 391
Tire ply material ............................ 393
Tire and loading terminology......... 393
Rotating tires ................................ 396
Winter driving ..................................... 398
Winter tires ................................... 398
Snow chains.................................. 399
Maintenance....................................... 400
Maintenance service indicator
message ....................................... 400
Calling up the maintenance
service indicator display ............... 402
Resetting the maintenance
service indicator ........................... 402
Vehicle care........................................ 403
Cleaning and care of the vehicle ... 403
Practical hints.................................. 413
What to do if … ................................... 414
Lamps in instrument cluster ......... 414
Lamp in center console ................ 425
Vehicle status messages in the
multifunction display .................... 427
Where will I find ...? ............................ 467
First aid kit.................................... 467
Vehicle tool kit.............................. 467
Spare wheel .................................. 471
Unlocking / locking in an emergency .. 474
Unlocking the vehicle ................... 474
Locking the vehicle ....................... 475
Fuel filler flap ................................ 475
Resetting activated head restraints.... 477
Vehicles without Rear Seat
Entertainment Package................. 477
Vehicles with Rear Seat
Entertainment Package*............... 478
Replacing SmartKey batteries ............ 479
Replacing bulbs .................................. 480
Bulbs............................................. 480
Replacing bulbs for front lamps .... 483
Replacing bulbs for rear lamps ..... 487

Page 24 of 569

23 At a glance
Exterior view
ItemPage
1Tailgate119
Power tailgate*119
Cargo compartment
Loading instructions
Cargo tie-down rings
Hooks
Expanding
Cover blind
Cargo net*
289
290
291
292
299
301
Vehicle tool kit467
Spare wheel471
2Rear window defroster207
3Rear lamps481
4Fuel filler flap352
Refueling352
Fuel353,
540
ItemPage
5Exterior rear view mirrors
Adjusting48
Auto-dimming rear view
mirrors*203
Power folding*204
6Towing eye bolt467
Installing towing eye bolt515
7Tires and wheels363,
529
Checking tire inflation
pressure373
General information363
Flat tire492
Spare wheel471
8Hood
Opening356
Engine oil358
Coolant360
ItemPage
9Windshield wipers59
Wiper blades, replacing489
Wiper blades, cleaning409
aWindshield
Cleaning with wiper fluid61
Cleaning409
bPower tilt/sliding sunroof*248
Panorama roof with power
tilt/sliding panel*252
cDoors
Locking and unlocking110
Opening and closing118
Locking/unlocking in an
emergency474
dFront lamps480
eHeadlamp cleaning system*203

Page 356 of 569

355 Operation
At the gas station
Engine oil level
For more information on engine oil, see
“Engine oil” (
page 358).
Coolant
For normal replenishing, use water (pota-
ble water quality). For more information,
see “Coolant level” (
page 360) and
“Fuels, coolants, lubricants, etc.”
(
page 536).
Brake fluidWindshield/rear window washer
system and headlamp cleaning
system*
For more information on refilling the wash-
er reservoir, see “Windshield/rear window
washer system and headlamp cleaning
system*” (
page 362).
Vehicle lighting
Check function and cleanliness. For infor-
mation on replacing light bulbs, see “Re-
placing bulbs” (
page 480).
For more information, see “Exterior lamp
switch” (
page 143).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 373).
!If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum mark or
below, have the brake system checked for brake
pad thickness and leaks immediately. Contact an
authorized Mercedes-Benz Light Truck Center
immediately. Do not add brake fluid as this will
not solve the problem. For more information, see
“Brake fluid” (
page 539).

Page 361 of 569

360 Operation
Engine compartment
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
Screw filler cap1 back on filler neck.
For more information on engine oil, see
“Technical data” section (
page 536) and
(
page 538).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Light
Truck Center check the automatic trans-
mission.Coolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground.
!Excess oil must be siphoned or drained off.
It could cause damage to the engine or
emission control system not covered by the
Mercedes-Benz Limited Warranty.
Warning!G
In order to avoid any potentially serious
burns:
Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature display
indicates that the coolant is overheated.
Do not remove pressure cap on coolant
reservoir if coolant temperature is
above 158°F (70°C). Allow engine to
cool down before removing cap. The
coolant reservoir contains hot fluid and
is under pressure.
Using a rag, slowly open the cap approx-
imately 1/2turn to relieve excess pres-
sure. If opened immediately, scalding


Page 395 of 569

394 Operation
Tires and wheels
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 3 hours or
driven no more than 1 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 (Department of Transportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross Axle Weight Rating)
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 Trailer Weight)
The GTW is the weight of the trailer plus
the weight of all cargo, equipment, luggage
etc. loaded on the trailer. GVW (G
ross Vehicle Weight)
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 GVW must never exceed the
GVWR indicated on the certification label
located on the driver’s door B-pillar.
GVWR (G
ross Vehicle Weight Rating)
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 certi-
fication label located on the driver’s door
B-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to 1 psi; another metric unit for air
pressure is bars. There are 100 kilopascals
(kPa) to 1 bar.

Page 541 of 569

540 Technical data
Fuels, coolants, lubricants, etc.
Fuel requirements
Gasoline engine
Only use premium unleaded fuel.
The octane number (posted at the
pump) must be 91 min. It is an
average of both the Research Octane
Number (RON) and the Motor Octane
Number (MON): (RON+MON) /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.
Diesel engine
Only use commercially available vehicular
ULTRA-LOW SULFUR HIGHWAY DIESEL
FUEL (15 ppm SULFUR MAXIMUM).
To prevent malfunctions, diesel fuel with
improved cold flow characteristics is
offered in the winter months. Check with
your fuel retailer.
Gasoline additives (gasoline engine)
A major concern among engine
manufacturers is carbon build-up caused
by gasoline. 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 loss
!Do not fill the tank with gasoline. Do not
blend diesel fuel with gasoline or kerosine.
The fuel system and engine will otherwise be
damaged, which is not covered by the
Mercedes-Benz Limited Warranty.

Page 564 of 569

563 Index
Technical data 538
Air conditioning refrigerant 538
Brake fluid 537, 539
Coolant 537, 541
Dimensions, Vehicle 534
Electrical system 533
Engine 527
Engine oil 536, 538
Engine oil additives 538
Fuel requirements 540
Fuels, coolants, lubricants, etc. 536
Gasoline additives 540
Premium unleaded gasoline 539
Rims 529
Tires 529
Weights 535
Windshield washer and headlamp
cleaning* system 538, 544
Tele Aid* 322
Call priority 328
Emergency calls 323
Hands-free microphone 33
Information 326
Initiating an emergency call
manually 324Messages in the multifunction
display 461
Remote door unlock 328
Roadside Assistance 325
SOS button 324
Stolen Vehicle Recovery
services 329
System self-check 323
Telephone* 319
Answering a call 188
Changing mobile phone cradle 321
Dialing a number from the phone
book 188
Ending a call 188
Hands-free microphone 33
Inserting in cradle 320
Installing a different mobile phone
cradle 321
Messages in the multifunction
display 461
Operation 187
Phone book* 188
Redialing 189
Rejecting an incoming call 188
Removing from cradle 321Temperature
Coolant 164
Display mode, Status indicator 175
Interior temperature, setting see Cli-
mate control or Automatic climate
control (3-zone)*
Outside temperature 165
Sensor, Interior temperature 225
Sensor, Outside temperature 155
Tether attachment points
Children in the vehicle 87
3-zone automatic climate control* 222
Ticket holder 309
Tie-down rings 290
Tightening torque, Wheel bolts 501
Tilt/sliding panel* see Panorama roof with
power tilt/sliding panel*
Tilt/sliding sunroof* see Power tilt/sliding
sunroof*
Time 176
TIN 388, 395
Tire and Loading Information
Placard 367
Terminology 393
Tire Identification Number see TIN
Tire inflation pressure