That star wheel adjuster would have standard threads ( not reversed like some rear wheel adjusters ) so you need to determine, what would lengthen the adjuster, moving the star up or down, if you can see the threads it would help. remember block the wheels before you go under.
Usual manual brake adjustment would work, adjust the star wheel till it stops then back up 7 clicks, then test the feel of the e brake pedal. If the pedal stops higher off the floor than before adjustment your good.
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.