Grease/Oil the part of the arm that rolls on the roller, and oil the roller. Most of mine the roller has not worked very well, but as long as it slides the door will close and not bind. If it binds enough it will bend the part with the roller back. Actually, looking at the picture it looks like yours already has done that some and it might be binding on the part that doesn't roll. Maybe see if you can get it back straight with a little prybar action.
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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)
MEPR: Man, my 4x4 makes all other LUVs look good
