Rear Diff Bushing Install - Lessons learned

Originally Posted by 40 to 332

Have put on approximately 1000 miles since installing the Z1 polyurethane rear differential bushings. No noticeable difference in noise or vibration. However, on a recent inspection, I noticed that the rear bushing appears to have eased rearward slightly (i.e., less than 1/8") in the subframe. Is this type of movement within normal limits? There is no gap between the mating surfaces of the differential and the rear bushing and all bolts/nuts were torqued to spec when the new bushings were installed. Thanks in advance for any input.