Mercedes-Benz 2005 M-Class Operator's Manual page 319

Technical data
Fuels, coolants, lubricants, etc.
If the coolant level is low, water and
MB 325.0 anticorrosion/antifreeze
should be used to bring it up to the proper
level (have cooling system checked for
signs of leakage). Please make sure the
mixture is in accordance with label instruc-
tions.
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 an authorized Mercedes-Benz Light
Truck Center.
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