1997 MERCEDES-BENZ ML320 engine

294 Technical dataEngine
EngineModel
ML 350 (163.157
1)
1The quoted data apply only to the standard vehicle. See an authorized Mercedes-Benz Light Truck Center for the corresponding data of all special bodies and special
equipment.
ML 500 (163.175)
1
Engine
112
113
Mode of operation
4-stroke engine, gasoline injection
4-stroke engine, gasoline injection
No. of cylinders
6
8
Bore
3.81 in (97.00 mm)
3.81 in (97.00 mm)
Stroke
3.31 in (84.00 mm)
3.31 in (84.00 mm)
Total piston displacement
227 cu in (3724 cm
3)
303 cu in (4966 cm
3)
Compression ratio
10:1
10:1
Output acc. to SAE J 1349
232 hp / 5750 rpm
(173 kW / 5750 rpm)
288 hp / 5600 rpm
(215 kW / 5600 rpm)
Maximum torque acc. to SAE J 1349
254 lb-ft / 3000-4500 rpm
(345 Nm / 3000-4500 rpm)
325lb-ft/2700rpm
(440 Nm / 2700 rpm)
Maximum engine speed
6000 rpm
6000 rpm
Firing order
1-4-3-6-2-5
1-5-4-2-6-3-7-8
Poly-V-belt
2370 mm
2370 mm

300 Technical dataFuels, coolants, lubricants etc.
Fuels, coolants, lubricants etc.Capacities
Vehicle components and their respective
lubricants must match.Therefore use only brands tested and
approved by Mercedes-Benz.Please refer to the Factory Approved
Service Products pamphlet, or inquire at
your Mercedes-Benz Light Truck Center.
Model
Capacity
Fuels, coolants, lubricants etc.
Engine with oil filter
ML 350, ML 500
8.5 US qt (8.0 l)
Approved engine oils
Automatic transmis-
sion
9.0 US qt (8.5 l)
MB Automatic Transmission Oil
Transfer case
1.6 US qt (1.5 l)
(Dexron 3 or Dexron 2E)
Rear axle
1.3 US qt (1.25 l)
(Hypoid gear oil SAE 90, 85 W 90)
Front axle
1.2 US qt (1.1 l)
(Hypoid gear oil SAE 90)
Power steering
approx. 0.65 US qt (0.6 l)
MB Power Steering Fluid
Front wheel hubs
approx. 1.5oz (43g) each
High temperature roller bearing grease

302 Technical dataFuels, coolants, lubricants etc.Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, use
only engine oils approved by
Mercedes-Benz. Information on approved
engine oils is available in the Factory
Approved Service Products pamphlet, or at
your authorized Mercedes-Benz Light
Truck Center.
Engine oil additives
Do not blend oil additives with engine oil.
They may damage the engine.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil is used in the air condition-
ing system.
Never use R-12 (CFC) or mineral-based lu-
bricating oil. Otherwise damage to the
system will occur.
Brake fluid
During vehicle operation, the boiling point
of the brake fluid is continuously reduced
through the absorption of moisture from
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be re-
placed every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Light Truck
Center will provide you with additional in-
formation.
!Always check the oil filler cap
(page 221) for important information
pertaining to the engine oil needing to
meet a specific Mercedes-Benz specifi-
cation (e.g. MB 229.5). If such informa-
tion is printed on the oil filler cap, only
use an engine oil from the list of ap-
proved engine oils in the Factory Ap-
proved Service Products pamphlet that
meets the specification indicated on
the oil filler cap.
Using engine oils of other specification
may cause the FSS to incorrectly deter-
mine the next service interval and will
result in engine damage not covered by
the Mercedes-Benz Limited Warranty.

303 Technical data
Fuels, coolants, lubricants etc.
Premium unleaded gasoline
Fuel requirements
Use only premium unleaded meeting
ASTM standard D 439:

The octane number (posted at the
p um p) m us t be 91 mi n. It i s an a vera ge
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 depos-
its.
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 en-
gine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking / pinging


Misfire


Power loss
Do not blend other specific fuel additives
with fuel. This only results in unnecessary
costs and may be harmful to the engine
operation.
!To maintain the engine’s durability and
performance, premium unleaded gaso-
l i n e m u s t b e u s e d . I f p r e m i u m u n l e a d e d
is not available and low octane fuel is
used, follow these precautions:

Have the fuel tank only partially
filled with unleaded regular and fill
up with premium unleaded as soon
as possible.


Avoid full throttle driving and abrupt
acceleration.


Do not exceed an engine speed of
3000 rpm if the vehicle is loaded
with a light load such as two per-
sons and no luggage.


Do not exceed
2/3 of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.

304 Technical dataFuels, coolants, lubricants etc.Damage or malfunctions resulting from
poor fuel quality or from blending specific
fuel additives are not covered by the
Mercedes-Benz Limited Warranty.Coolants
The engine coolant is a mixture of water
and anticorrosion / antifreeze, which pro-
vides:

Corrosion protection


Freeze protection


Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -35°F (-37°C) and corro-
sion protection.
If the antifreeze mixture is effective to
-22°F (-30°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).The coolant solution must be used year
round to provide the necessary corrosion
protection and increase in boil-over pro-
tection. Refer to Service Booklet for
replacement interval.
To provide important corrosion protection,
the solution must be at least 45%
anticorrosion / antifreeze (equivalent to
freeze protection to approx. - 22°F
[-30°C]). If you use a solution that is more
than 55% anticorrosion / antifreeze (freeze
protection to approx. - 49°F [-45°C]), the
engine temperature will increase due to
the lower heat transfer capability of the so-
lution. Therefore, do not use more than
this amount of anticorrosion / antifreeze.If the coolant level is low, water and MB
anticorrosion / antifreeze should be used
to bring it up to the proper level (have cool-
ing system checked for signs of leakage).
Please make sure the mixture is in accor-
dance with label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, con-
sult your authorized Mercedes-Benz Light
Truck Center.

305 Technical data
Fuels, coolants, lubricants etc.
Anticorrosion / antifreeze
Your vehicle contains a number of alumi-
num parts. The use of aluminum compo-
nents in motor vehicle engines
necessitates that
anticorrosion / antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. (Failure to use
such anticorrosion / antifreeze coolant will
result in a significantly shortened service
life.)
Therefore, the following product is strongly
recommended for use in your vehicle:
Mercedes-Benz Anticorrosion / Antifreeze
agent.
Before the start of the winter season (or
once a year in hot southern regions), you
should have the anticorrosion / antifreeze
concentration checked. The coolant is also
regularly checked each time you bring your
vehicle to your authorized Mercedes-Benz
Light Truck Center for service.

307 Technical data
Fuels, coolants, lubricants etc.
Windshield washer system and headlamp cleaning system*
Both the windshield washer and headlamp
cleaning system* are supplied from the
windshield washer fluid reservoir.
The windshield and headlamp washer fluid
reservoir has a capacity of approx.
8.0 US qt (7.6 l).
Refill the reservoir with MB Windshield
Washer Concentrate “S” and water (or
concentrate and commercially avail-
able premixed windshield washer
solvent / antifreeze, depending on am-
bient temperatures).Windshield and headlamp washer fluid
mixing ratio
For temperatures above freezing, use
MB Windshield Washer Concentrate “S”
and water:

1 part “S” to 100 parts water
[40 ml “S” to 1 gallon (4 liters) water].
For temperatures below freezing, use
MB Windshield Washer Concentrate “S”
and commercially available premixed
windshield washer solvent / antifreeze:


1part “S” to 100parts solvent
[40 ml “S” to 1 gallon (4 liters) solvent].
Warning!
G
Washer solvent / antifreeze is highly flam-
mable. Do not spill washer
solvent / antifreeze on hot engine parts, be-
cause it may ignite and burn. You could be
seriously burned.

311 Technical terms
ABS
(A
ntilock B
rake S
ystem)
Prevents the wheels from locking up
during braking so that the vehicle can
continue to be steered.
BabySmart
TM airbag deactivation
system
This system detects if a special system
compatible child restraint seat is in-
stalled on the front passenger seat. The
system will automatically deactivate
the passenger front airbag when such a
seat is properly installed (indicator
lamp7 in the instrument cluster
lights up). See your authorized
Mercedes-Benz Light Truck Center for
availability.
BabySmartTM compatible child seats
Special restraint system for children.
The sensor system for the passenger
seat prevents deployment of the pas-
senger front airbag if a BabySmart
TM
compatible child seat is installed.BAS
(B
rake A
ssist S
ystem)
System for potentially reducing braking
distances in emergency braking situa-
tions. The system is activated when it
senses an emergency based on how
fast the brake is applied.
Bi-Xenon headlamps*
Headlamps which use an electric arc as
the light source and produce a more in-
tense light than filament headlamps.
Bi-Xenon headlamps produce low
beam and high beam.
CAC
(C
ustomer A
ssistance C
enter)
Mercedes-Benz customer service cen-
ter, which can help you with any ques-
tions about your vehicle and provide
assistance in the event of a break-
down.CAN system
(C
ontroller A
rea N
etwork)
Data bus network serving to control ve-
hicle functions such as door locking or
windshield wiping.
Cockpit
All instruments, switches, buttons and
indicator / warning lamps in the pas-
senger compartment needed for vehi-
cle operation and monitoring.
Cruise control
Driving convenience system for auto-
matically maintaining the vehicle speed
set by the driver.
Engine number
The number set by the manufacturer
and placed on the cylinder block to
uniquely identify each engine pro-
duced.