I just replaced my differential mount. Yes, it fixed the rear sag problem!! One of the 4 13mm bolts that hold it into position on the subframe snapped off inside the subframe while removing the old mount. Is there a way to get that piece out of the hollow subframe member so I can replace the bolt (assuming the threaded insert is ok...I suspect it may be rusted, thus the break)? Are bolts 3 enough to hold the mount in place?