The Rear right differential side seal failed under 40K miles and car was out of manufacturer warranty and I had to pay to get the seal and bearing replaced. I cannot believe a seal and bearing need to be rep[laced withing 40K miles. I had to replace a seal on the Transfer case last year when the car was still under manufacturer’s warranty. My guess is that poor quality of the seals/bearings or improper installation procedures could have led to these early failures and surely warrants an investigation.