314 OperationDriving instructionsTrailer towing Trailer hitches*
Only install a trailer hitch receiver ap-
proved for your vehicle.
For information on availability and in-
stallation, see an authorized
Mercedes-Benz Light Truck Center.
The bumpers on your vehicle are not
designed for use with clamp-type hitch-
es.
Do not attach rental hitches or other
bumper-type hitches to them.
To reduce the possibility of damage, re-
move the hitch ball adaptor from the
receiver when not in use.Electrical connections
The vehicle is prewired to accept the sev-
en-wire harness included in the
Mercedes-Benz approved trailer hitch re-
ceiver kit.
An additional four-pole conversion plug is
included in the Mercedes-Benz supplied
trailer hitch receiver kit.
For further information, see an authorized
Mercedes-Benz Light Truck Center.
Warning!
G
Failure to use proper equipment and driving
technique can result in a loss of vehicle con-
trol when towing a trailer.
Improper towing or failure to follow the in-
structions contained in this guide can result
in vehicle damage and/or serious personal
injury. Follow the guidelines below carefully
to assure safe trailer operation.
Ask an authorized Mercedes-Benz Light
Truck Center should you require an explana-
tion of information contained in this guide.
315 Operation
Driving instructions
Vehicle and trailer weights and ratings
Gross Vehicle Weight Rating (GVWR) is the
maximum permissible vehicle weight:
6240 lbs (2830 kg).
Gross Vehicle Weight (GVW):
Comprises weight of vehicle including fuel,
tools, spare wheel, installed accessories,
passengers, cargo and trailer tongue. It
must never exceed the GVWR.
Gross Axle Weight Rating (GAWR) is the
maximum permissible axle weight:
The Gross Trailer Weight (GTW) is the
weight of the trailer plus the weight of all
cargo, equipment, luggage etc. loaded on
the trailer. The maximum permissible
gross trailer weight to be towed:
5000 lbs (2260 kg).Trailer Tongue Weight Rating (TWR) is the
maximum permissible weight on the trailer
tongue:
500 lbs (225 kg) limit for Mercedes-Benz
approved hitch receiver.
Loading a trailer
When loading a trailer, you should ob-
serve that neither the permissible GTW,
nor the GVWR are exceeded.
Maximum permissible values are listed
on the safety compliance certification
labels for the vehicle and for the trailer
to be towed.
The lowest value listed must be select-
ed when determining how the vehicle
and trailer are loaded.
The tongue weight at the hitch ball
must be added to the GVW to prevent
exceeding your Mercedes-Benz tow
vehicle’s rear GAWR.Checking weights of vehicle and trailer
To assure that the tow vehicle and trail-
er are in compliance with the maximum
permissible weight limits have the load-
ed rig (tow vehicle including driver, pas-
sengers and cargo, trailer fully loaded)
weighed on a commercial scale.
Check the vehicle’s front and rear
Gross Axle Weight (GAW), the GTW and
TW.
The values as measures must not
exceed the weight limits listed under
“Vehicle and trailer weight and ratings”
(page 315).
ML 350
ML 500
Front
2945 lbs
(1335 kg)
2985 lbs
(1355 kg)
Rear
3295 lbs
(1495 kg)
3255 lbs
(1475 kg)
iWe recommend loading the trailer in
such a manner that it has a tongue
weight (TW) between 10% and 15% of
the GTW.
316 OperationDriving instructionsAttaching a trailer
Observe maximum permitted trailer
dimensions (width and length).
Most states and all Canadian provinces
require
safety chains between your tow vehicle
and the trailer.
The chains should be criss-crossed
under the trailer tongue. They must be
attached to the hitch receiver, and not
to the vehicle’s bumper or axle.
Make sure to leave enough slack in the
chains to permit turning corners.
a separate brake system at various
trailer weights.
a break-away switch on trailers with a
separate brake system.
The switch activates the trailer brakes
in the possible event that the trailer
might separate from the tow vehicle.
Start the engine (
page 34).
Make sure the automatic transmission
is set toP.
Set the parking brake for the vehicle
(page 52).
Vehicles with ADS*: Set the vehicle
level to Highway (
page 250).
Vehicle with ADS*: Set the ADS* to
AUTO or COMFORT (
page 249).
Stop the engine (
page 34).
Attach the trailer.
!Do not connect a trailer brake system
(if trailer is so equipped) directly to the
vehicle’s hydraulic brake system, as
your vehicle is equipped with antilock
brakes. If you do, neither the vehicle’s
brakes nor the trailer’s brakes will func-
tion properly.iThe provided vehicle electrical wiring
harness for trailer towing has a brake
signal wire (color orange) for hook-up
to a brake controller.
You should consider using a trailer
sway control system. For further infor-
mation see an authorized
Mercedes-Benz Light Truck Center.
Warning!
G
Vehicles with ADS*:
Do not lock or unlock any doors or the tail-
gate while attaching or uncoupling the trail-
er. Do not open or close any doors or the
tailgate while attaching or uncoupling the
trailer. Make sure no one operates the ADS*
switch (
page 249) or the vehicle level
control* switch (
page 252) while a trailer
is being attached or uncoupled. The vehicle
level could change, and you could injure
yourself and/or others.
317 Operation
Driving instructions
Plug in all electrical connectors.
Towing a trailer
There are many different laws, including
speed limit restrictions, having to do with
trailer towing. Make sure your rig will be le-
gal, not only for where you reside, but also
for where you will be driving. A good
source for this information can be the po-
lice or local authorities.
Note the following points, when driving
with the trailer:
In order to gain skill and an under-
standing of the vehicle’s behavior, you
should practice turning, stopping and
backing up in an area which is free from
traffic.
Before you start driving check the
trailer hitch
break-away switch
safety chains
electrical connections
lighting and tires
Adjust the mirrors to permit unobstructed
view beyond rear of trailer.
If the trailer has electric brakes, start
your vehicle and trailer moving slowly,
and then apply only the trailer brake
controller by hand to make sure the
brakes are working properly.
Always secure items in the trailer to
prevent load shifts while driving.
When towing a trailer, check occasion-
ally to make sure the load is secure,
and that lighting and trailer brakes (if
so equipped) are functioning properly.
Take into consideration that when tow-
ing a trailer, the handling characteris-
tics are different and less stable from
those when operating the vehicle with-
out a trailer.
It is important to avoid sudden maneu-
vers.
The vehicle and trailer combination is
heavier, and therefore is limited in ac-
celeration and climbing ability, and re-
quires longer stopping distances.
It is more prone to reacting to cross
wind gusts, and requires more sensi-
tive steering input.
If possible, do not brake abruptly, but
rather engage the brake slightly at first
to permit the trailer to activate its
brake. Then increase the braking force.
iWhen you are towing a trailer, the vehi-
cle level always remains in the Highway
setting.
318 OperationDriving instructions
If the transmission hunts between
gears on inclines, manually shift to a
lower gear (select 4, 3, 2 or 1).
A lower gear and reduction of speed re-
duces the chance of engine overload-
ing and/or overheating.
On very steep inclines, not manageable
with automatic transmission in1,
switch on off-road driving program
(page 248).
When going down a long hill, shift into
a lower gear and use the engine’s brak-
ing effect.
Avoid riding the brakes, thus overheat-
ing the vehicle and trailer brakes.
If the engine coolant rises to an ex-
tremely high temperature (coolant tem-
perature needle approaching the red
zone) when the air conditioning is on,
turn off the air conditioning system.
Engine coolant heat can be additionally
vented by opening the windows,
switching the climate control fan speed
to high and setting the temperature
control to the maximum hot position.
Extreme care must be exercised since
your vehicle with a trailer will require
additional passing distance ahead than
when driving without a trailer.
Because your vehicle and trailer is
longer than your vehicle alone, you will
also need to go much farther ahead of
the passed vehicle before you can re-
turn to your lane.Uncoupling the trailer
Start the engine (
page 34).
Make sure the automatic transmission
is set toP.
Set the parking brake for the vehicle
(page 52) and for the trailer.
Close all doors and the tailgate.
Detach the trailer immediately after-
ward as follows:
Disconnect all electrical plug connec-
tors.
Uncouple the trailer.
!If the trailer should begin to sway, re-
duce the vehicle’s speed immediately.
In no case attempt to straighten out the
tow vehicle and trailer by increasing
the speed.
319 Operation
Driving instructions
Make sure that the trailer coupling is
free of load.
Stop the engine (
page 34).
Passenger compartment
Driving abroad
Abroad, there is an extensive
Mercedes-Benz service network at your
disposal. If you plan to drive into areas
which are not listed in the index of your
Mercedes-Benz Light Truck Center directo-
ry, you should request pertinent informa-
tion from an authorized Mercedes-Benz
Light Truck Center.
Warning!
G
As soon as you disconnect the electrical
connection between the trailer and the
vehicle, the vehicle will lower. To help avoid
personal injury, make sure no one is near
the wheel housing or underneath the vehicle
before the electrical connection is discon-
nected.
When you uncouple the trailer, the vehicle is
temporarily raised because the springs are
relieved of load. Be especially careful during
this process, as you could otherwise injure
yourself and/or others. Make sure that any
persons remaining in the vehicle do not
press the switches for vehicle level control*
or the ADS*.
Warning!
G
Always fasten items being carried as secure-
ly as possible.
In an accident, during hard braking or sud-
den maneuvers, loose items will be thrown
around inside the vehicle, and cause injury
to vehicle occupants unless the items are
securely fastened in the vehicle.
The rear cargo compartment is the preferred
place to carry objects. Always use the parti-
tion net when transporting cargo. Partition
net cannot secure hard or heavy objects. Al-
ways fasten items being carried as securely
as possible using the cargo tie-down rings in
the cargo floor area and fastening materials.
340 OperationTires and wheelsThe placard showing the load limit informa-
tion is located on the driver’s door B-pillar.
If your vehicle is equipped with the Tire and
Loading Information placard (Example A),
locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or XXX lbs.”
on this placard. The combined weight of all
occupants, cargo/luggage and trailer
tongue load (if applicable) should never
exceed the weight referenced in that
statement.
Placard (Example B)
1Load limit information on the Vehicle
Tire Information placardThe placard showing the load limit informa-
tion is located on the driver’s door B-pillar.
If your vehicle is equipped with the Vehicle
Tire Information placard (Example B),
locate the heading “Vehicle Capacity
Weight” on this placard. The combined
weight of all occupants, cargo/luggage
and trailer tongue (if applicable) should
never exceed the weight listed next to
vehicle capacity weight.
Seating capacity
The seating capacity gives you important
information on the number of occupants
that can be in the vehicle. Observe front
and rear seating capacity. Depending on
production date, your vehicle may be
equipped with placard Example A or
placard Example B.
Your vehicle may not be equipped with
placard A nor other placard posting the
seating capacity. If this is the case, legal
requirements at time of production of your
vehicle did not require manufacturers to
post the seating capacity.Never let more people ride in the vehicle
than there are designated seating posi-
tions and seat belts available. Be sure ev-
eryone riding in the vehicle is correctly
restrained with a separate seat belt.
iData shown on placard examples are
for illustration purposes only. Seating
data are specific to each vehicle and
may vary from data shown in the illus-
trations below. Refer to placard on ve-
hicle for actual data specific to your
vehicle.
342 OperationTires and wheelsStep 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 344).
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 1500 lbs. This is for illustration
purposes only. Make sure you are using
the actual load limit for your vehicle stated
on the vehicle’s placard (
page 339).