AC ? On my 2000 freightliner classic

You must remove the ft. cover of a/c box to ck. if the drip tube is still lipped over inside edge of box if a crack is found in tube a new rubber tube or put repair sealer in crack?

 

Probably need to drain refrigerant and remove the evaporator. Those year and make trucks the evaporator clogs up big time as well as the drain area.

 

This is what a dirty evaporator looks like. FLD120 are famous for clogging up. You need to take it to a shop that can recover your refrigerant and take the evaporator out and clean it properly.

 

Dirty??? That looks like a brick!

 

My old mechanic would take an air hose and blow out that drip tube really good. But you probably did that.