Does it cycle every time you slow down?

It uses a variable reluctor sensor which uses the tone ring (pressed onto the ring gear) to create a "sine-wave" that the ABS/RWAL module uses. At higher speeds the signal is very strong and very frequesnt. At lower speeds the signal gets weaker as does the frequency. If the signal goes to zero quickly vs. counting down to zero, the module will think the wheels have locked and will go into an ABS/RWAL cycle.

It is possible the new sensor is to far away from the tone ring causing the signal to drop from a low speed to zero. I do not remember the air gap between the sensor and the tone ring. You may need a service manual for that gap information.

Also, there is the possibility that as the old sensor came apart in the differential you could have chipped a tooth on the tone ring. You can see inside the sensor hole and spin the rear axle to make sure each tooth is present and accounted for. I do not know if the tone ring is a replaceable item or not?

Good Luck!