jack up the rear, take off the tires, take off the drums, see if visually anything is wrong, if the adjusters need to be adjusted, etc. also you may need adjust the slack in the e-brake cable. I dunno if you can even adjust it, but on other vehicles i've worked on, there was a nut on a metal bracket thing you could turn to take out slack in the e-brake cable. never looked on my t100 tho since mine works fine