As a way to increase braking performance, the brake pads and rotors are make of a softer material and may be in need of replacement after approximately 20,000 miles; owners should be vigilant about getting their brakes checked.Google+
Car Problem Reports
Mercedes-Benz GL450 Soft Braking Components May Wear After 20,000 Miles
Mercedes-Benz GL450 Problem
Average Mileage: 28,203 mi (5,000 mi - 50,100 mi)
Visitor, 2013 Mercedes-Benz GL450
Have had to replace rotors at 7,000, 20,000 and 30,000.
Visitor, 2013 Mercedes-Benz GL450, 5,000 mi
Had to replace rotors at 5000 and at 15000 miles on 2013 GL450
Visitor, 2007 Mercedes-Benz GL450
I have less than 50,000 and will be replacing again shortly.
Visitor, 2010 Mercedes-Benz GL450, 22,000 mi
the brakes wear out very quickly always brake dust on front rims looks crappy
Visitor, 2011 Mercedes-Benz GL450, 32,000 mi
HEARD SQUEAKING ON FRONT BRAKES AND WAS TOLD THE PADS AND ROTERS NEEDED TO BE REPLACED. AMAZING. I HAVE NEVER HEARD OF A NEWER CARE NEEDING ROTERS DONE.
Visitor, 2007 Mercedes-Benz GL450, 50,100 mi
Brake pads worn out in 20K miles - need to be replaced