Mercedes-Benz 2004 G 500 Operator's Manual page 338

Technical data
Fuels, coolants, lubricants, etc.
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
Anticorrosion/antifreeze quantity
Model Approx. freeze protection
– 35°F (– 37°C)
G 500/ 6.35 US qt (6.0 l)
G 55 AMG
338
regularly checked each time you bring your
vehicle to your authorized Mercedes-Benz
Light Truck Center for service.
– 49°F (– 45°C)
7.0 US qt (6.6 l)