I was heart broken when I took my wife's Jeep Grand Cherokee to our regular mechanic for a minor repair, check up and oil change and was told that at 100,000 miles she needed a new rear differential and it would be between $2500-$3000 dollars to replace with a remanufactured unit and would be down for 3-5 days. Jeep jeep as we affectionately refer to her is like my wife's baby, but that repair would have been so costly as to make it senseless to keep. I had thought about changing the gearing in my mustang at one time and remembered coming across AZ Driveshaft & Differential and just how great the reviews were so I gave them a call. They were able to get us in within a couple of days. When I booked the appointment they said they could pop the case open for around $150 for an inspection and would have closed it back up if we decided not to do the work. The verdict... $763 after the discount for checking in on Yelp I noticed posted on the counter! So yes for potentially 1/4 of the cost. It has been a few months and Jeep jeep is still going strong! Thanks AZD&D you guys really saved the day.