Hi there, I need to replace the front rotors on a 2002 ml500.... cannot get it out.. thanks

 

Not sure if the same, but i have a 2001 ml320 and have just had to do my front rotors/pads, a piece of cake, compared so some i`ve done
Open up the caliper by prying it against the rotor with a screw driver or simular, (compressing the piston back into the caliper[take care brake fluid doesnt spill out of resivoir]) flick out the outboard pad. remove the 2 caliper retaining bolts at the rear of the caliper (torx head) lift the caliper free, pull out the inner pad, the pads should be labelled lh/rh. The rotor is held onto the hub by a small torx head countersunk screw, i had bash the rotor with a hammer to free it from the hub.
Make sure you clean the new rotor free of all oil/grease and handle with clean hands from then on. Check fluid level and youre good to go, allowing for bedding in of new rotors/pads.