I don't have a Ram 3500 but do own a 1996 V10 Ram 2500 the rotors can be a real pain. They say you can hammer them off but that didn't work for me I removed the main axle nut and put to floor jacks pried against the frame and that popped of the rotor. Gook luck it's a pain, very stupid design dumb engineers.
first take off frontwheel then take off brake caliper then rotor will pull right off .
Remove caliper, pull rotor off hub, push new one on.
remove the distributor cap and grab the rotor then pull straight up.
under the rotor in the distributor unplug the wires take off the rotor and pull it out
The fuel filter will pull out of the canister when removed.
It's either a rotor (disc brake) or drum (Drum brake) either way you have to remove the wheel for both, for drum it takes a firm rap with a dead blow around the side of the drum and then should pull off. For Disc Brakes you remove the caliper and pads the the same goes for the rotor gentle tapping on the back side and it should come free. The rotor is bolted to the inside of th e wheel hub on a 3500. You need to remove the brake caliper, axle shaft, and wheel hub.
pull the wheel off, remove the two caliper bolts, remove the caliper and the rotor can be removed
Remove caliper and pull rotor off the hub. Push new one on, replace caliper and pads.
take the front clips out so you can take the front finders off
pull the wheel, and the caliper, you do not have to pull the big nut in the middle. after pulling the caliper the rotor will slip right off.
Dissasemble the hub the pull off the rotor with the lugs then use a hamer to punch out the lugs out of the rotor
The min thickness should be stamped on the backside of the rotor, pull and examine.