For best results I'd start a new thread w/ model & serial #'s & a complete description of your symptoms.

...I know this is an old post, but what did you end up finding with your issue? We are having a customer with the SAMe issue! I brought the drums back today and cut them and it almost seems like it made it worse! All new wheel cylinders and brakes and brake hardware were done in Dec 2013 and customer said this just all happaned out of the blue. I will check the backing plates Swoop, and see if they are hanging up the shoes

so you have a tight pedal but brakes will not apply?
it sounds to me like some kind of problem in the wheels maybe?
did you check the backing plates when you replaced the shoes?
sometimes they wear grooves where the shoes ride and these grooves will actually keep the shoes from moving, even though you have a seemingly good pedal.

try pulling the wheels & hubs and rechecking this
if you do find worn grooves on the backing plates they will have to be replaced.
I would also double check the hardware configuration and make sure your guys got it put together correctly, make sure the wheel cylinder rods are connecting to the shoes correctly etc.

Have you used a DOT 4 or 5 brake fluid.

i know when they pulled the drums off the old brake shoes had caused a "lid" inside the drums making it tough to get them off. they "dremeled" out that lip so my guess is they drums are smooth... Looks like the need roughed up.

Yes it might, sounds like the drums are glazed heavily and need either scuffed up good to take the glazing off or better yet turned down just a bit to true them up and take the glazing off just don't turn the down past their max ID,this should be stamped someplace on the drum

So if I'm understanding you correctly, you have a good, high,hard pedal- it just doesn't stop when you stand on the brakes. Did you cut the brake drums, rough them up or do nothing at all to the drums? If you did nothing, this is the reason for your issue. The compounds of the brake shoes these days require the drums to be at least roughed up or they'll take forever to seat.

Scuffing the shoes isn't really the answer, I'd spend your time getting the drums cut. Even when you're done with that the shoes will still take some time to "bite"- this has been my experience. What brand of shoe did you install- Hyster brand or aftermarket?

We replaced the master cylindr, wheel cylinder, shoes, everything.... We have pedal but you can stand on them and it still doesnt stop the truck. It is a S30XL. We were told to scuff the drum and pads in different direction? any idea if that will work?

replaced the master cylinder but not the wheel cylinders? How did they look...also how did the drums look... scored? worn??

How tight did you make the adjustment on the brake shoes & how much freeplay is in the brake pedal before it contacts the pushrod in the master cylinder?

Is it an S30A or S30XL?