Chevy Disc Swap Question

[Shulaps]

Hello,

Great site here, probably read about 1000posts for every one I post up. Incredible amount of info here (too much sometimes).

I am the usually suspect with 2 EB's as parts, 1 in build process and my daily driver.

Anyways, I have a line on a parts Chev in the right vintage ('72-early'77). Its a 3/4 ton and some of the reading I have gone through says you can use the 3/4 for the swap and others say it has to be a 1/2 ton.
Has anyone used 3/4 ton parts for the swap? If so does it need to be a light 3/4 ton or???

Any info would help.

Bill

 

[Pa PITT]

I DON'T THINK THE 3/4 TON WILL WORK. I see no way it could work. I've done 2 setups. & packed the wheel bearing on my Broncos about 30 times over the years .
.. & when I 1st packed my 73 I thought to my self . These thing will interchange . That was a good 10 years ago & sure enough it became available of the parts it takes to do the swap.
.....................
...Now some that use the dana 60 I guess they use the 3/4 ton & up stuff But not on the little Bronco front end

 

[broncnaz]

You need 1/2 ton parts. pre 77. 3/4 ton has larger spindles about the only thing that is the same is the calipers. I believe the backing plates on the 3/4 ton are larger as well so they cant be used either in the end its not worth the effort of tearing into a 3/4ton axle you get nothing.

 

[Shulaps]

http://www.broncodriver.com/images/pdf/dana30.pdf

This was the website I was looking at that mentioned the 3/4 stuff. I found it odd but thought I would check here and see if it was right. I think I may have read it somewhere else as well.

No problem, keep the search going for a donor, I am a little ways off that stage on the build.

Might just buy the new stuff but I kinda dig the old school approach to the disc brakes.

Bill

 

[ntsqd]

Just to state the obvious, 3/4t is 8 lug. So right away the wheel hubs won't work. Then the 8 lug trucks have a larger OD rotor, which means that a 15" wheel may or may not (probably not) fit, even if you solve the 5 lug to 8 lug issue. Because of that large rotor OD the caliper brackets are bigger too. They only work with that rotor OD and not with the 1/2t's smaller rotor OD.

 

[broncnaz]

Yeah I dont think Id trust using 3/4 ton parts maybe they are the same but Its doubtful 3/4 ton rotors are larger not a lot but larger(maybe 1/2") so that means the caliper bracket will be taller as well. Not that could be a benefit in a way as you may not have to clearance your knuckles as much but then again you may loose some brake pad contact on the rotor. Spindles well they could be the same but from my research they use larger bearings. Of course there is a way around that if you want to have the spindle machined to small bearing specs. It has been rumored that there were small bearing spindles on some 3/4 ton D44's but most likely you wont see that in 77.
Unless you got the axle free and could check the fitment Id pass until you find the 1/2ton parts.

 

[Broncotj0]

Remember you can use all the blazer parts also. I used '75 blazer spindle, backing plates and calipers on mine with '76 ford discs.

 

[Viperwolf1]

Yeah I dont think Id trust using 3/4 ton parts maybe they are the same but Its doubtful 3/4 ton rotors are larger not a lot but larger(maybe 1/2") so that means the caliper bracket will be taller as well. Not that could be a benefit in a way as you may not have to clearance your knuckles as much but then again you may loose some brake pad contact on the rotor. Spindles well they could be the same but from my research they use larger bearings. Of course there is a way around that if you want to have the spindle machined to small bearing specs. It has been rumored that there were small bearing spindles on some 3/4 ton D44's but most likely you wont see that in 77.
Unless you got the axle free and could check the fitment Id pass until you find the 1/2ton parts.

My research also concluded calipers were the same but spindles were not. http://classicbroncos.com/disc-list.shtml

 

[Shulaps]

Makes sense that why I asked. I recall back in the day the assortment of 1/2 tons heavy half's light 3/4 ect. and figured that maybe it may work.

Back to looking for that rusting gold in someone's back yard.

Thanks,

Bill

 

[Pa PITT]

... As was said it's 1/2 ton truck ... Blazers & Submarines.. Suburbans...
..I say it's 73.5 & 74 year models. Others say some other years fit but not on mine.

 

[broncnaz]

Years should be up to 76 in 77 the spindle changed to a larger inner bearing and also 10 bolt instead of D44 although the backing plates and calipers stayed the same. Spindles will work with some machining. But thats extra $$ unless you can dop it yourself or have access.