One problem related to brake disc has been reported for the 2005 Mercedes Benz ML500. The most recently reported issues are listed below.
Ml500 eats through brakes. El dorado hills mercedes replaced brakes and rotors on my Ml500 at 29000 when I purchased the vehicle, since then they have had to replace the brakes and rotors 3 times and I only have 60000 on the vehicle and most of that was highway driving. I do not pull anything, no trailer hitch installed. Appears to be design flaw or I'm being taken by the dealer.