Here's the update with some background:
Since the local garage here is a truck garage, my M1009 is filler-work there. To date, the emergency brake lines, rear drums, brake cylinders, brake lines are all new due to age, Pennsylvania road salt and the new & improved Pennsylvania liquid road salt.
The DOT3 brake fluid has not yet been replaced with DOT5. I went to the garage today and the left rear drum was pulled for me to look at as mechanic explained how he photographed the original brake arrangement and duplicated the installation with the new parts.
After the lock-up with the new parts, listed above, the mechanic pulled both drums and found that the adjusters had traveled their full distance such that the brake shoes were in constant contact with the drum [so heat, expansion, & lock-up]. He hypothesized [his expertise is in heavy trucks with air brakes] that the removed adjusters were in backwards so he switched them. He has driven the machine and the brakes appear to be functioning fine.
I drove the Blazer around the lot to bring it in and out of the garage and the 'feel' of the pedal and braking action seemed improved [although it drove great after the initial brake work for the first few miles]. The blazer is still at the garage to have the brake fluid changed out and to be tested further to see if the problem was found and the fix made.
I will keep you updated. And, thank you for the comments/feedback/hints.
I do tend to do a very good job when I rebuild brakes . Sometimes I just get carried away. But I never seen a worn out backing plate. Except the time my right rear axle broke on my M1009 and I drove home in 4 HI with the right rear backing plate dragging on the ground. New axle backing plate and we were back on the road. A backing plate is good for about 3 miles till the axle will hit the road. Lesson learned.
