Yes, a broken semi truck axle can be repaired, but it will likely require a professional. The first step is to assess the damage. If the axle is bent, it will need to be replaced. However, if the axle is simply cracked, it can be welded back together. There are three main types of welding that can be used for this repair: oxy-acetylene welding, arc welding, and mig welding. Each has its own benefits and drawbacks, so itâs important to consult with a professional before deciding which one is right for your needs.