The contact owned a 2019 Volvo Truck VNL. The contact stated that the check engine warning light was illuminated intermittently. The contact stated that while the driver was driving approximately 50 mph when they noticed the rear axle smoking. They pulled to the side of the road where they attempted to detach the trailer. The smoke became an actual fire. The fire department was called and extinguished the fire. A report was filed. The vehicle was deemed totaled and was towed. There were no injuries and no medical assistance was needed. The contact did not speak with the dealer. The manufacturer was not made aware of the failure. The approximate failure mileage was unknown.