2002 Subaru Outback axlel leakage question

Yes. They are probably talking about the axle cv boot is leaking grease and happens often. If you catch it early you can just replace the axle cv boot but if its been leaking for a while then you will have to replace the axle assembly. If the boot is torn open then you will need to address it, if its just seeping then dont worry about it. The tell tale sign of a bad axle will be clicking noises when turning tight corners and accelerating. Dont panic, even at this stage the axle can still be driven on for a long time, sometimes even years.