My truck is cdl because it has Air brakes.
Having air brakes on a vehicle that is less than 26,001 doesnt require it to be cdl.
CDL is determined by usage of the vehicle as well as weight.
Vehicle wt, Hazmat or passengers (16) determine if the vehicle requires air brakes then the operator is required to have the endorsement.
If your registered axel wt is more than 26,001 you will need the cdl.
But, having a vehicle that has a gvw under 26,001 with air brakes
doesnt necessarily mean cdl.