Drivers side rear brake locks up.

Could be a number of things. First I would try the adjuster on the brakes. Adjust so that the shoes are almost touching the drum but not. Also did you change the springs on the brake assembly? Weak springs can cause this. Another thing to look for is to have brake shoes and the inside of drum perfectly clean. Use brake cleaner and remove any fluid or grease on the shoes and drum.

Did notice an abnormal build up of brake dust on bottom of one shoe and top of other one. (build up was on new shoes after a couple weeks of use) Cleaned this off and seemed to help for a day or two. Did not replace the springs, will check into that. Checked adjuster but truthfully just set it close enough to ease the drum back on. Relied on backing car up and applying brake to set adjuster. This is probably my problem. Thanks for your help.

Yes that is a good method on the adjustment, but the closer you get it to the correct position right away the better. It takes a lot of applying the brakes in reverse to get any amount of adjustment. On the adjuster...make sure you clean and lube it well. It should turn freely.

Ok thanks. Any ideas about the added build up on the shoes? Will be taking it apart again today and the build up will probably be back on them. Have taken apart twice since new shoes were put on and both times there was this build up.

Buildup means wear. You have brakes that are either set too tight or brake cylinder not returning properly. With the drum off have someone push brake pedal watch the shoes they should come out smooth and return quickly and smoothly

Just got it back together. To my surprise no build up this time. But drum appeared to have a wax like coating on it. Other than that all looked good. Shoes were adjusted just so drum would slide off without hanging on shoes. Cleaned drum real well and lightly buffed with sand paper to remove coating. No major wear or scratches to drum or shoes. If this doesn't fix I will check operation of shoes as you advised the next time I remove drum. Again thanks for your help.

Test drive went well. No sounds or locking up. Maybe we got it this time.

Great

sounds like bad calipers to me