I towed a bunch of boats with my 72 k5. IIRC, it had a 12 bolt in it and other than shaking loose a ring gear bolt while I was camping out in the cuts, it towed just fine. I was also towing small 2K lb hot rod jet boats.
My '63 K15 had a Dana 44 rear axle (I think) which I swapped out to a Dana 60 - 8 lug rear with 4.10s. At the time I would tow a smallish 4,500 lb comp ski boat and it did fine but had better braking than the smaller axle.
The last incarnation involved installing a 14bff with factory discs, 4.11 and the Gov Lok. It has been in since 2017 or so and has done fine although I think that the Dana 60 might have had better braking. Maybe I just need hydro boost?
The boat that I pull now is around 5,500 lbs before the wife and kids throw all of the stuff in it (extra 1k lbs.)and no fuel. Usually have around 1,500 in the bed as well. Usual tow is 3-4 hrs through the valley and up into the foothills.
In my humble opinion, for braking alone, I wouldn't go back to a 12 bolt or a Dana 44 (I wouldn't even consider a 10b) but really think that the 14b with discs might have been a little over rated (for the brakes). Maybe drums would have been better? Maybe user error on my part in the set up. The 60 with the big drums was a real nice axle that started its life of abuse long before i got it and was abused as long as I had it. I tortured that thing with some of the loads it hauled. Never a peep from it and it always stopped real well.
Anyone know what size brakes are on the 12b vs the 14b SF?
The older I get, my tolerance for not having good binders while towing has waned a bit. Ive puckered plenty of bench seats into needing new upholstery
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Whatever youre gonna run, get the biggest brakes offered on them and keep them in tip top shape. Or get a real good set of rip stop seat covers and a kick arse upholsterer buddy!
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