When you buy a New Heavy Duty Truck Everything is New. Checking your camshafts and slack adjusters are a major factor in brake wear. By Checking your Heavy Duty Truck camshafts I do not mean shacking it up and down and saying "It's still snug".
Check it with a Dial Guage with a magnetic base like this one..
Making sure that there is no more than 10 thousands of an inch in mouvment in your Heavy Duty Truck s-cam . If you have more than that you will need to either replace your cam bushing or your cam itself. Make Sure that the neck of the cam that is usualy on the inside of the spider is not wore as well a this will also affect your braking perfomance.
Thanks And Stay Tuned To Heavy Duty Tuck Parts