Volvo Repair: Replacing front wheel bearing, air impact wrench, volvo 850 turbo wagon

Question
I have a 1996 Volvo 850 turbo wagon and the passenger wheel bearing is making a low tone hum sound.  I've tried removing the front 36mm axle nut with a small breaker bar and bent it still not loosening the nut.  Can you suggest how I can get this off and then how to back the splin out as I presume it will also be stuck..  For the nut would renting an electric impact wrench work.  I've been putting liquid wrench on the nut hoping it would help.  Also what is the torque setting when replacing the nut?
Thanks

Answer
I use an air impact wrench.I am not sure an electric one will work.the axle can become very stuck in the hub.if you are going to hit it hit the nut.turn the nut off till it is past the threads and hit it this will keep from damaging the threads.the torque setting is as tight as my gun will tighten it.I do not torque it so I am usure of the spec for this and we are not working tomorrow due to the hurricane(I am in SW Florida) so I can not check on it.