Looking for brake 3/4 advice/parts

[soloveyart]

I have a 1971 3/4 K20 4x4 and my stock brakes need replacing/upgrade. Does anyone know of where to find either replacement drum brake components or a 8 lug nut disc brake conversion kit? My stock rear end is a Spicer 10 Bolt Corporate. Haven't had much luck so far.
Thanks
Michael Solovey

[Mudder]

Welcome to the site. I moved this over to the 4x4 area. I believe you will get some better answers here. Not sure which ones it is but some of those trucks are impossible to find brake parts for. These guys will chime in. Again welcome to the site.

[Burt4x4]

10 bolt in a 71?
If it were me I would not spend a dime on that 10bolt.
Pick up a 14FF rear, disk brake conversions are getting cheeper nowa days as lots of fab places make conversion kits fo the 14bolt rears.

Get some pics posted up ~ we love pictures! hehehehe

[Yukon Jack]

Welcome to the board from another Kansan. Can you get a pic of the rear axle, as I'm wondering if it has an Eaton HO52 rather than what you describe as a 10 bolt.

[soloveyart]

Appreciate the feedback. Will get some pictures posted once I figure out how to do that.

The rear end is definately a 10-bolt, perfectly round like half a basketball. What is a 14FF? I assume a different type of rear end. I have no problem with getting a new rear end, but I need to find something where I can keep my 8 lug patterned-wheels. More to follow. Thanks again

[Yukon Jack]

Perfectly round like this in this pic is an Eaton HO52 - not what is classically referred to as a 10 Bolt. The Eaton is a strong unit while the 10 bolt is considered a bit weak. The Eaton had a factory Detroit Locker called the No-Spin as an option. A 14 bolt disk brake kit is said t work on the Eaton axle.

[ERASER5]

An Eaton HO has 10 bolts on the inspection plate and on the other side the third member bolts in like a Ford 9 inch. Drums for an Eaton are hard to come by and expensive when you find them. A disc conversion my be the best bet.

A Dana 60 also has 10 bolts on the inspection cover, but the cover plate in not round like the Eaton.

A true "10 bolt" is the little sister to the GM 12 bolt and it is a 5 lug 1/2 ton unit.

[special-K]

I bought everything from Napa.These are great rears.A 14-bolt FF is the rear that replaced these in`73.FF is for full floating.There is a later 14-bolt that is a semi-full floater with a 1" smaller ring gear.The 14-boltFF is another legendary rear.They are available in 3.73:1,a notch taller than the HO52s were avaolable with.

[soloveyart]

This is great feedback. Really appreciate the info. Been wrestling with this brake deal for too long. So if I understand correctly, a 14FF axle with a 3.71:1 gear ratio is the way to go for a 3/4 Ton 4x4 to support even my 454? If that is the case, I would image Summit Racing would either have a drum brake kit or disc brake kit to accommodate a 8 lug-nut set-up.

Does anyone know of someone selling a 14FF axle?

Thanks again. Michael

[ghettoluxury]

Originally Posted by soloveyart

This is great feedback. Really appreciate the info. Been wrestling with this brake deal for too long. So if I understand correctly, a 14FF axle with a 3.71:1 gear ratio is the way to go for a 3/4 Ton 4x4 to support even my 454? If that is the case, I would image Summit Racing would either have a drum brake kit or disc brake kit to accommodate a 8 lug-nut set-up.

Does anyone know of someone selling a 14FF axle?

Thanks again. Michael

the 14 bolt was in 3/4 ton from 73 to 87 and 1 tons from 73 to 91 almost any junk yard should have one. and if you dont mind not having an e-brake then a disc brake conversion is cheep and easy with mounting bracket for around $50 and some calipers and rotors from a front dana 44 of these same years

[4x4Poet]

Originally Posted by soloveyart

...So if I understand correctly, a 14FF axle with a 3.71:1 gear ratio is the way to go for a 3/4 Ton 4x4 to support even my 454? If that is the case, I would image Summit Racing would either have a drum brake kit or disc brake kit to accommodate a 8 lug-nut set-up.

Does anyone know of someone selling a 14FF axle?...

I think you missed Yukon Jack's point. You used the term "10-bolt" to describe the axle under your 3/4 ton when a GM "10-bolt" rear 4x4 axle has 6-lug hubs and a cast pumpkin with pressed in axle tubes. GM "10-bolt" half ton axles never came on a '71, let alone a 3/4 ton. You likely have a 3/4 ton Eaton H052 axle that just happens to have a diff cover that also has 10 bolts. Tell us if the photos above show what you have under your truck.

An H052 axle is, IMO, superior to a 14bFF for a pickup. The H052 is lighter than a 14bFF and thereby gives a superior ride. 14bFFs are so heavy that under 67-72 pickups they make the rearend almost hop over bumps as that extra weight gets thrown upward. Not unruly, just inferior to lighter H052s.

Also, your truck's H052 ring gear likely has a thrust stop to hinder ring gear deflection under heavy loads. It can handle a 454 in a pickup all day long. You'll break traction before breaking a serviceable H052 before a 14bFF would break.

Like specialK posted, the drum brake parts are available thru auto parts stores. As already suggested, a disc brake conversion is a better option if the budget allows. Costs about double a DIY drum brake job, but check for yourself. Less if you source some parts locally. Still less if you keep the truck long since disc parts wear better. Less hassle to change pads down the road, too. A disc conversion reduces unsprung weight for and even better ride. Those drums are heavy compared to rotors.

blackbirdscustomtrucks sells H052 rear disc conversion kits. Board member, too.

From what I understand from other board members, Blackbirds' disc caliper bracket uses spacers, while ruffstuffspecialties offers a bracket that needs no spacers. Should be cheapest to buy the bracket you prefer and source the other parts needed locally. A search should find threads with the parts lists. The vendors may help with a list of parts needed if you buy their bracket.

Bottom line: There's no brake parts costs or BBC torque needs that warrant swapping the H052 for a 14bFF. Personal preference is another matter.

[ghettoluxury]

4x4poet thanks for adding the link to ruffstuffspecialties those are the brackets I am running on my 82 and it is a simple swap throw in now rotors for about $40 each, calipers $20 each, and pads $14 and you have rear disc brakes for under $200

[71GMChevy]

I have been doing a lot of research on this myself... I don't want to fix the drum brakes and I dont want to spend over 500 bucks on a rear disc kit. I have a dana60 and i can't find someone that just sells the brackets so I am making my own.

But on a 14ff and eaton, it seems like there are tons of brackets out there that use stock front discs and calipers from the k20. I tried going with the whole 78 caddy rear caliper idea with the disc brake built in but it just didnt seem like it would work that well. I'm going to put a driveline/cutting brake on the truck instead because in california we have too many hills.

Thats just what I have come up with. Let me know if anyone has a better idea.