The transmission in my 99 ML420 failed at 85,000 miles as I pulled up to a red light in downtown Toronto. I was 2,000 miles from home so this was an expensive event. It limped along for 6 blocks or so before there was no connection whatsoever between the engine and the wheels.

When the pan was pulled, there were large chunks of broken gears in it. Apparently this "sprag failure" is not entirely uncommon on 98 and 99 MLs.

Fluid had been changed at 45,000.