Mercedes-Benz 2005 M-Class Operator's Manual page 214

Operation
Driving instructions
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.
212
Vehicle and trailer weights and ratings
Gross Vehicle Weight Rating (GVWR) is the
maximum permissible vehicle weight:
6614 lbs (3000 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:
front 2976 lbs (1350 kg)
rear 3858 lbs (1750 kg)
Gross Trailer Weight (GTW) is the maxi-
mum permissible 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.
i
We recommend loading the trailer in
such a manner that it has a tongue
weight (TW) between 10% and 15% of
the GTW.