Here's some additions from a fairly new tractor/trailer tech myself.

Davco filter wrenchs (different trucks have different sizes). Get Lisle ones off Amazon, look exactly the same as Matcos

Long barrel air hammer (harbor freight has them now) especially if you work on rust belt trucks.

Filter wrenches you can use a 1/2 breaker bar/long ratchet for stubborn air dryer filters and fuel/oil filters. I have gearwrench ones from Amazon.

https://www.amazon.com/GearWrench-2321-Heavy-Filter-Wrench/dp/B000JFN9MM/ref=mp_s_a_1_3?dchild=1&keywords=gearwrench+filter+wrench&qid=1609170432&sprefix=gearwrench+filter&sr=8-3

Get a harbor freight pry bar, cut a notch in the end so it looks like a fork and you got yourself a 10 dollar return spring (big spring) installer tool for air drum brakes.

A clipboard for paperwork