Your axles have rubber boots on them and over time with any piece of rubber it deteriorates and the boot will crack and tear. When this happens it's time to replace your axle. Unfortunately the boot it's self is not replaceable typically because once the boot is torn dirt and debris can get into the grease causing damage to the internal parts of your axle. It can also cause noise and after a period of time all of the grease will come out and the axle will break.
If you have front end noise give us a call or request an appointment online and we will get you back on the road.