octane MERCEDES-BENZ ML320 1997 Complete Repair Manual

11 IntroductionChange of address or ownership
If you change your address, be sure to send in the “Change of Address Notice” found in the Service and Warranty
Information Booklet, or simply call the Mercedes-Benz Client Assistance Center (in the USA) at
1-800-FOR-MERCedes, or Customer Service (in Canada) at 1-800-387-0100. It is in your own interest that we can
contact you should the need arise.
If you sell your Mercedes, please leave all literature with the vehicle to make it available to the next operator.
If you bought this vehicle used, be sure to send in the “Notice of Purchase of Used Car” found in the Service and
Warranty Information Booklet, or call the Mercedes-Benz Client Assistance Center (in the USA) at
1-800-FOR-MERCedes, or Customer Service (in Canada) at 1-800-387-0100.
Operating your vehicle outside the USA or Canada
If you plan to operate your vehicle in foreign countries, please be aware that:
•Service facilities or replacement parts may not be readily available,
•unleaded gasoline for vehicles with catalytic converters may not be available; the use of leaded fuels will damage
the catalysts,
•gasoline may have a considerably lower octane rating, and improper fuel can cause engine damage.

213 What you should know at the gas station
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Leaving the engine running and the fuel cap open can
cause the “CHECK ENGINE” lamp to illuminate.
Fuel tank capacity approximately 19.0 US gal (72.0 l).
This includes approximately 3.2 US gal (12.0 l) reserve.
Use premium unleaded gasoline: Posted Octane
Index 91 (Average of 96 RON / 86 MON).
•Engine oil
Engine oil level check, see page 89 and page 233.
Fill quantity between upper and lower dipstick
marking level: 2.1 US qt (2.0 l).
Recommended engine oils, see Approved Service
Products sheet.• Coolant
For normal replenishing, use water (potable water
quality).
For further information (e.g. anticorrosion/
antifreeze), see page 292.
• Spark plugs
Approved spark plugs, see page 290.
• Tire pressure
For tire pressure, refer to tire pressure label inside
the fuel filler flap. See page 250 for further details.
• Air conditioner
R-134a refrigerant and special PAG lubricant, see
page 294.
Wa r n i n g !
Overfilling of fuel tank may result in creating
pressure in the system which could cause a gas
discharge such as the gas spraying back out upon
removing the filler nozzle which could cause
personal injury.

293 Fuels, coolants, lubricants etc. - capacities
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Brake system
(MB Brake fluid [DOT 4+])approx. 0.9 US qt (0.8 l)
Windshield / headlamp washer system
(MB Windshield washer concentrate “S”
1)Vehicles without
headlamp cleaning
system
Vehicles with headlamp
cleaning systemapprox. 5.5 US qt (5.0 l)
approx. 8.0 US qt (7.6 l)
Cooling system
(MB Anticorrosion / antifreeze)approx. 12.7 US qt (12.0 l)
Fuel tank
including a reserve of
(Premium unleaded gasoline:
Posted Octane 91 (Avg. of 96 RON / 86 MON))ML 320 / ML 430
ML 55 AMGapprox. 19.2 US gal (73.0 l)
approx. 3.2 US gal (12.0 l)
approx. 24.5 US gal (93.0 l)
approx. 3.2 US gal (12.0 l)
Air conditioner system
(R-134a refrigerant and special
PA C l u b r i c a n t (Never R-12))
1 Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing or MB Windshield Washer Concentrate “S” and
commercially available premixed windshield washer solvent / antifreeze for temperatures below freezing. Follow suggested mixing ratios, see
page 237.Fuels, coolants, lubricants etc. Model Capacity

295 Fuels, coolants, lubricants etc.
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Premium unleaded gasoline
Caution!
To maintain the engine’s durability and performance,
premium unleaded gasoline must be used. If premium
unleaded is not available and low octane fuel is used,
follow these precautions:
•have the fuel tank filled only partially 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
persons and no luggage,
•do not exceed 2 / 3 of maximum accelerator pedal
position, if the vehicle is fully loaded or operating in
mountainous terrain.Fuel requirements
Use only Premium unleaded meeting ASTM
standard D 439:
The octane number (posted at the pump) must be
91 min. It is an average of both the Research (R) octane
number and the Motor (M) octane number: [(R+M) / 2].
This is also known as 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 not to 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..

11
Introduction Change of address or ownership
If you change your address, be sure to send in the “Change of Address Notice” found in the Service and Warranty
Information Booklet, or simply call the Mercedes-Benz Client Assistance Center (in the USA) at
1-800-FOR-MERCedes, or Customer Service (in Canada) at 1-800-387-0100. It is in your own interest that we can
contact you should the need arise.
If you sell your Mercedes, please leave all literature with the vehicle to make it available to the next operator.
If you bought this vehicle used, be sure to send in the “Notice of Purchase of Used Car” found in the Service and
Warranty Information Booklet, or call the Mercedes-Benz Client Assistance Center (in the USA) at
1-800-FOR-MERCedes, or Customer Service (in Canada) at 1-800-387-0100.
Operating your vehicle outside the USA or Canada
If you plan to operate your vehicle in foreign countries, please be aware that: • Service facilities or replacement parts may not be readily available,
• unleaded gasoline for vehicles with catalytic converters may not be available; the use of leaded fuels will damage
the catalysts,
• gasoline may have a considerably lower octane rating, and improper fuel can cause engine damage.

213
What you should know at the gas station
Te ch n ica l
data
Instruments
and controls Operation
Driving Instrument
cluster display Practical hints Car care Index
Leaving the engine running and the fuel cap open can
cause the “CHECK ENGINE” lamp to illuminate.
Fuel tank capacity approximately 19.0 US gal (72.0 l).
This includes approximately 3.2 US gal (12.0 l) reserve.
Use premium unleaded gasoline: Posted Octane
Index 91 (Average of 96 RON / 86 MON).
•Engine oil Engine oil level check, see page 89 and page 233.
Fill quantity between upper and lower dipstick
marking level: 2.1 US qt (2.0 l).
Recommended engine oils, see Approved Service
Products sheet. • Coolant
For normal replenishing, use water (potable water
quality).
For further information (e.g. anticorrosion/
antifreeze), see page 292.
• Spark plugs Approved spark plugs, see page 290.
• Tire pressure For tire pressure, refer to tire pressure label inside
the fuel filler flap. See page 250 for further details.
• Air conditioner R-134a refrigerant and special PAG lubricant, see
page 294.
Wa r n i n g !
Overfilling of fuel tank may result in creating
pressure in the system which could cause a gas
discharge such as the gas spraying back out upon
removing the filler nozzle which could cause
personal injury.

293
Fuels, coolants, lubricants etc. - capacities
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints Car care Index
Brake system
(MB Brake fluid [DOT 4+]) approx. 0.9 US qt (0.8 l)
Windshield / headlamp washer system
(MB Windshield washer concentrate “S”
1) Vehicles without
headlamp cleaning
system
Vehicles with headlamp
cleaning system approx. 5.5 US qt (5.0 l)
approx. 8.0 US qt (7.6 l)
Cooling system
(MB Anticorrosion / antifreeze) approx. 12.7 US qt (12.0 l)
Fuel tank
including a reserve of
(Premium unleaded gasoline:
Posted Octane 91 (Avg. of 96 RON / 86 MON)) ML 320 / ML 430
ML 55 AMG approx. 19.2 US gal (73.0 l)
approx. 3.2 US gal (12.0 l)
approx. 24.5 US gal (93.0 l)
approx. 3.2 US gal (12.0 l)
Air conditioner system
(R-134a refrigerant and special
PA C l u b r i c a n t (Never R-12))
1 Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing or MB Windshield Washer Concentrate “S” and
commercially available premixed windshield washer solvent / antifreeze for temperatures below freezing. Follow suggested mixing r atios, see
page 237.Fuels, coolants, lubricants etc. Model Capacity

295
Fuels, coolants, lubricants etc.
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints Car care Index
Premium unleaded gasoline
Caution!
To maintain the engine’s durability and performance,
premium unleaded gasoline must be used. If premium
unleaded is not available and low octane fuel is used,
follow these precautions:
• have the fuel tank filled only partially 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
persons and no luggage,
• do not exceed 2 / 3 of maximum accelerator pedal
position, if the vehicle is fully loaded or operating in
mountainous terrain. Fuel requirements
Use only Premium unleaded meeting ASTM
standard D 439:
The octane number (posted at the pump) must be
91 min. It is an average of both the Research (R) octane
number and the Motor (M) octane number: [(R+M) / 2].
This is also known as 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 not to 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..

13 Introduction
Operator’s Manual
Change of address or ownership
If you change your address, be sure to
send in the “Change of Address Notice”
found in the Service and Warranty Informa-
tion Booklet, or simply call the
Mercedes-Benz Customer Assistance
Center (in the USA) at
1-800-FOR-MERCedes, or Customer Ser-
vice (in Canada) at 1-800-387-0100. It is in
your own interest that we can contact you
should the need arise.
If you sell your Mercedes, please leave all
literature with the vehicle to make it avail-
able to the next operator.
If you bought this vehicle used, be sure to
send in the “Notice of Purchase of Used
Truck” found in the Service and Warranty
Information Booklet, or call the
Mercedes-Benz Customer Assistance Cen-
ter (in the USA) at 1-800-FOR-MERCedes,
or Customer Service (in Canada) at
1-800-387-0100.Operating your vehicle outside the USA
or Canada
If you plan to operate your vehicle in for-
eign countries, please be aware that:

service facilities or replacement parts
may not be readily available,


unleaded gasoline for vehicles with cat-
alytic converters may not be available;
the use of leaded fuels will damage the
catalysts,


gasoline may have a considerably low-
er octane rating, and improper fuel can
cause engine damage.

215 Operation
At the gas station

Replace the fuel cap by turning it to the
right.
You will hear when the fuel cap is tight-
ened.

Close the fuel filler flap.
Check regularly and before a long trip
Open the hood (
page 217)
1Engine oil level
2Coolant level
For normal replenishing, use water (po-
table water quality). More information
on the coolant level can be found in the
“Operation” section (
page 222).
3Brake fluid
4Windshield washer system and
headlamp cleaning system*
More information on filling the reser-
voir can be found in the “Operation”
section (
page 224).
iUse only premium unleaded gasoline
with a minimum Posted Octane Rating
of 91 (average of 96 RON / 86 MON).
Information on gasoline quality can
normally be found on the fuel pump.
More information on gasoline can be
found in the Factory Approved Service
Products pamphlet.
iLeaving the engine running and the fuel
cap open can cause the yellow fuel
tank reserve warning lamp to flash and
the? lamp to illuminate.
See also “Practical hints” section
(page 248).