With a dual master cylinder and a power booster, my stock drums haul my 715 to a stop relatively well for a 40+ year old truck of that weight with a big V8 and lots of extra gear in it.
Almost every truck I've seen or had my hands on has had at least a couple wheel cylinders inoperative, a questionable master cylinder, and improperly adjusted brakes. Get all that fixed and even in stock form, for the limits the truck was designed to operate in, they work acceptably.
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