The normal way the brakes adjust are when going in reverse and the brakes are applied then this causes the shoes to move enough to pull the adjuster cable and ratchet the adjsuter, the only way it could be adjusting when going forward would be for the shoes to be installed wrong, short shoes go towards front, long shoes toward back, or the adjuster cable installed on the front shoe instead of the back. Thats it .. Its not a complicated system.
Ford Technician
Ford senior master and ase master certified 19years Ford dealership experience