speed sensor

The Vehicle Speed sensor is located on top of the differential housing. it is held in with one bolt and takes about 15 minutes to change. Part #56028 187AC. Always have the dealership check and verify for the latest updated part number. REMOVAL: Raise vehicle on hoist. Remove brake line mounting nut and remove the brake line from the sensor stud. Remove mounting stud from the sensor and shield Rear Speed Sensor Mounting . Remove sensor and shield from differential housing. INSTALLATION: Connect harness to sensor. Be sure seal is securely in place between sensor and wiring connector. Install O-ring on sensor (if removed) Insert sensor in differential housing. Install sensor shield. Install the sensor mounting stud and tighten to 24 N·m (18 ft. lbs.). Install the brake line on the sensor stud and install the nut. Lower vehicle.

I also have a 1998 dodge ram 2500 and the same thing happened to me and all I had to do is replace the abs sensor that is located at the rear axle. It is not your speed sensor trust me it is way cheaper.

it could b the one on the back of ur tran or t case depending on if it's 4x4 or not but all u need is a 1 inch deep socket to do that

i also have the same problem with speedometer i was told it had no vss single witch is on left side of trany so i change it still no speedometer i then change speedometer not it so i got a book started look for the problem well i havent fix it but do know what happen there should be 5 volts at vss on trany book says check vss wire at computer should have 5 volts replace computer if no volt if it has 5 volts at computer check wire from computer to vss on trany for broken wire dont know if this will help but check for the 5 volts at vss vss is a two wire pulg left side of trany just in front off transfer 4 wheel drive or end of trany case 2 wheel drive if you have 5 volts at vss change vss i well let you know what i find out about mine when i get it working