i am trying to buy brake rotors for my 1994 dodge ram 2500 4x4 and i was wondering do i have the 3500lb or 4500lb front axle?

 

you should be able to get the axle weight rating off the tag on the door jam where the vin is. should have gross veh weight ratings and axle ratings as long as long as you can still read it, and nobody has swapped an axle before you got the truck. i think the 8800lbs gvwr is the heavy duty one