As of 2014 in the United States, the average cost of repairing a broken axle is anywhere from $75 to $150 per axle and can increase to $150 to $300 per axle if the work is done by a professional mechanic. Vehicles with four-wheel drive are usually more expensive to repair.
The axle might be in need of repair if the vehicle starts vibrating as it's being driven. If the axle is not the problem, then it could be that something is out of alignment. It is best that a broken axle be inspected and repaired as soon as possible to avoid further damage.
If the axle's housing is cracked, then a new one may need to be installed, which increases the overall cost of the repair. Any damage that is done to the internal components of the vehicle can also increase the repair costs. Other factors that can influence the price of repairing a broken axle include the make and model of the vehicle, the mechanic, the auto shop, the axle gears that have been damaged and the complexity of the repair.
If only a single component of the axle is damaged, the repair costs can be much less. It is always best that major auto repairs be done by an experienced ASE certified auto mechanic.