I have a 07 Ford Edge that I have had the axle seal on the driver side replace 3 times already. The first time this happened just happened to be 1000 miles past the warrenty.The dealer said there not sure what would cause this to happen time and time again however they are covering the replacement of the parts and labor.
Front driver side axle seal leaking. on 2007 Ford Edge
There are many possible reasons why the halfshaft seal may be leaking repetitively. First, the technician removing the original seal may have scratched the seal mating surface in the case. Secondly, the seal may not be installed with the correct seal driver. Third, there may be damage to the halfshaft itself causing damage to the seal after driven for a while. These are the most common issues that I have come across. I hope this helps.