Keep in mind that there could also be leaking rear axle seals which could contribute to this condition. You might also check the parking brake linkage and cables as to the cause for the excessive wear on the rear brakes.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine