The AMG V8s are acknowledged as heavy premium-fuel drinkers, and at least one experienced owner singles out the brakes as the truck's real weak point, too small to haul down a near-three-ton rig quickly from highway speed. These are treated as accepted character traits rather than defects.
Fuel thirst and undersized brakes
Mercedes-Benz G55/G63 AMG (W463 2004-2018) · driving