But how do you know that the service brakes on the dolly and rear box are 100%? If I'm building a set I can tug test the front box before hooking up, if the wheels drag with the trolley bar down I know that the service brakes are working 100‰. Once I'm built doing the same thing for the whole set how do I know the dolly and rear box have 100% brake strength
you need someone to show you. another feeder driver or an on road.
like trickpony said it is part of your pre=trip. once you have hooked the whole set together set the parking brake and push in your red button to supply air to the whole set. pull down your trolley handle so you can check brake lights.
on your walk around , do your pre=trip from the front as usual. check all air line connections. you have already turned the valves on from the back trailer to supply air to the back , right. you should hear the air go. plus you are pushing in your snubber.
at the back of rear trailer , open up your valves one at a time and air should come out. this is a simplified version that you really can't learn from reading this. Have an experienced feeder driver walk you through it or ask an onroad to help you with it. There are a couple videos on you tube but they are not as good as UPS training.
This should be no problem for a professional truck driver to help you with this. We want you people to ask us questions if you are not sure. Remember you are driving a deadly weapon and you want to be completely sure you have it right before going on the highway. don't be pressured to hurry up by dispatch or anyone else.
ask, ask , ask . the best way to learn is watching a someone in person. a couple weeks of training is not enough and it's impossible trying to remember everything they throw at you in those two weeks.
a good driver is ALWAYS learning. everyday , every month , every year for 30-40 years. the day you think you know it all is the day you should quit.