The Power Of The Spring Brake

I hope this isn't a dumb question, but there is something I don't understand. Why does the power of the spring brakes depend on the proper adjustment of the service brakes? I thought the spring brakes were independent of the other mechanisms that functioned only when there is an emergency loss of air pressure. Thanks.

Doug, take a look at this page.

https://www.ontario.ca/document/official-air-brake-handbook/spring-parking-and-emergency-brake-subsystem

I hope this isn't a dumb question, but there is something I don't understand. Why does the power of the spring brakes depend on the proper adjustment of the service brakes? I thought the spring brakes were independent of the other mechanisms that functioned only when there is an emergency loss of air pressure. Thanks.

The service and emergency brakes use the same pads. The brake adjustment accounts for wear of the pads.

Doug, I know spring brakes are big with high school and college students

Duh...now I get it. Makes sense and is logical. Sometime it hard to see the forest for the trees! Thanks

Duh...now I get it. Makes sense and is logical. Sometime it hard to see the forest for the trees! Thanks

And basically the issue makes for a "trick question" on the exam!

Funny Bruce!

I'm planning on taking the test this week after the physical. Been studying this weekend.

Good luck Doug, I got dinged only on a couple of questions but the way they worded them was very confusing. You'll pass easy with the high road fresh in mind

Thanks Spaceman. I am not a good test taker normally. But we have a nice testing center. I have used the High Road a lot, in addition I have about 600 questions and answers that I've been using to quiz myself on. I made a notebook with pictures of trucks and important stuff to remember. I hope I pass it the first time, but if not I will take it until I get it right. I'll post what happens to me, the good or the bad.