2003 Volvo VNL, I am experiencing front brakes drag

Check or replace the Quick Release valve. You don't say if you have antilock brakes. In that case it may be a different valve.

 

Follow the line from each front brake chamber. They will go to a valve like the ones pictured or the QR may be part of the antilock valve. Once you find the valve (near the center of the front axle) follow the airline that feeds it to see if there is another valve. You can have a helper push on the brake pedal and then watch each brake to see what happens. Is there a delay in releasing? Also crawl under to see which valve exhausts and if that is releasing all at once or if it is slow causing the drag.

 

If they are over adjusting check the length of the new slacks holes against the old, 5" vs 5 1/2" would really ruin your day.
On some styles you have to set the adjuster pointer to the notch.
A couple of things to check.

 

Also, did you put standard 'Q' shoes on when they should have been 'Q+' ?