I looked at the 2013 manual and it apparently is in the maintenance reminder computer as a sub item. Doesn’t say how many miles though, I guess you just have to rely on the computer, but it does say 30K or 2 years if the car is being towed. You could use that I suppose if you wanted to ignore the computer. I change the rear diff fluid in my Ford truck about every 40-50 K miles, and has worked for me. However if I ever go through water high enough the diff is submerged then I change the fluid straight away.
"Code 6 ● Replace rear differential fluid*