Trailer Truck Brakes

dimanche 30 octobre 2016

I was watching a TV program the other night called Ice Road Truckers and saw trucks being towed without the air pressure being built up and the same with trailers. In the little corner of the world where I live that would be imposible cause without air pressure the brakes are locked on. Can someone please explain ( ozzies will get this).:D
I'm just curious and it's no big deal