the one on the front should be thicker and have more brake pad material covering the metal that the other shoe, also it may be a good idea to use the other side as a reference. good luck. i hope i helped and please accept my answer. thanks T-MAN
If you have never replaced the brakes on a truck before and you are not too familiar with the procedures involved, only dissemble and assemble one side at a time, leaving the other side intact as a reference during reassembly.
Interchanging the brake shoe adjusting screw assemblies from one side of the vehicle to the other would cause the brake shoes to retract rather than expand each time the automatic adjusting mechanism is operated. To prevent this, the socket end of the adjusting screw is stamped with an "R" or an "L" for "RIGHT" or "LEFT". The adjusting pivot nuts can be distinguished by the number of lines machined around the body of the nut; one line indicates left hand nut and two lines indicate a right hand nut.
If the automatic adjusting mechanism does not perform properly, check the following:
F-250 HD and F-350 Models
See Figures 15, 16 and 17
Fig. 15: Rear brakes used on the F-250 HD and F-350 Fig. 16: HD rear brakes used on the F-250 and F-350 Fig. 17: F-250, F-350 rear ledge single anchor brake components
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