HELP on 1966 C20 Wheels

[stsalvage]

I did my brakes in the junk hauling business ever 6 months I checked them for cracks on the brake shoes or just to blow out the brake dust.If they looked like they where getting low I would put a fresh new set of brake shoes in AI use to buy my bake shoes from a guys that would reline them.I get a sweet deal for 10.00 a set so i bought 3 extra sets and gave him my old shoes and other old brake liner shoes.All my wheel cylinders where new with new brake Rubber lines.I use to haul 2-4 tons her load.I would have CHP pull me over once every month to check my truck on the 10 freeway back in the 90's