MACK issued a recall on the CXU model

On certain vehicles, the air brake supply tank pressure release valve may not have been installed at time of assembly. This could allow brake system pressure to rise above allowable limits, potentially causing the air tank to rupture. This could cause a loss of air brake system pressure, resulting in an eventual loss of service brake function and an unintended application of the emergency brakes, and could pose a risk of injury to bystanders due to flying debris. Correction: Dealers will install a pressure release valve in the supply tank.