Help needed adjusting brakes

[Ksmith203]

Hi, my name is Kevin. I drive hook truck for an Akron Ohio container company called Estes Hauling. I drive a 2000 C7500 with. cat engine. I brought my truck home to clean it up and replace the tail lights. I notice my truck air brake does not hold like it used to. I figure the slack adjusters need adjusted but I am not sure how to do it so I joined this forum. I would appreciate any help you can offer. I would like to adjust them tomorrow since I have all the other work completed. I am mechanical but have worked mostly on fords. Here is what the truck I built looked like when finished and what I started with. So if you give me the basics I will be able to adjust the brakes. I looked at the slack adjusters and saw what I thought to be the stud to turn to adjust the brakes but thought I would make sure before I screwed up something.

[BIGG BOY]

Hi my name is mark im a truck driver how we adjust them 3/8 or 11 mm socket or wrench turn till brakes r tight to drum then back off 1/4 turn to do the front take a wooden tape front brakes should measure 1/4 from the back of the push rode if you have any problem be in akron on wed. the bolt you c on the slack adjuster is the one your looking for