I'm in awe of you muddy that you work on forklifts. The times I've had to work on mine I always lose skin off my knuckles and arms. I'm also not enough of a contortionist to reach some of the bolts. I have to find out why my brakes failed and fix them.
As far as your brakes, if you have good pedal there's really only a few things it could be....
Your shoes are wet, either from wheel cylinder leaking or axle seals leaking.
Or your shoes could out of adjustment or just be plan worn out.
The brakes on a forklift are almost identical setup to an automotive drum brakes system.
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