change 10" rear drum brakes to 11"

Tie rods, steering box, drag link, alignment.<br />
What tires fit, brands, sizes, beadlocks, etc.

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Stan
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change 10" rear drum brakes to 11"

Post by Stan » Tue Dec 30, 2014 8:53 am

I should know this but musta ate too many carbs over the Holidays or someone slipped me some decaf - :lol:
What would it take to change the rear drum brakes on the '68 from 10" to 11"?
Obviously the drums and the shoes . I assume the wheel cylinders are the same ; how bout the backing plates ?
Stan
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TonyNokes
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Post by TonyNokes » Thu Jan 01, 2015 4:16 pm

I think there are two different widths of shoes and they take different backing plates....
66' 5.8L SEFI Super Charged, 4R70W, 4.88, 35" BFG's. Hydroboost, D44 w/trac-lock, HD axles. 9" w/ARB, Dutchman axles, Trusses and Lincoln disks all around, F150 PS, factory PTO winch & bumper, 3.5" suspension lift, 2" body, 14" 7100's Bilstiens, CAGE arms & springs, TRO, OBA, Yorkston Trackbar conversion, 3 fuel tanks...

DirtDonk
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Post by DirtDonk » Mon Feb 02, 2015 5:05 pm

All of the above and maybe more.

The "For Sure" items first:
The backing plates for sure.
The drums for sure.
The wheel cylinders maybe (they're definitely not all the same)
Shoes and hardware of course.

The Maybe items:
Angle of the dangle on the hard lines possibly, if the wheel cylinders are different.
Axle shafts if the drum offset is different enough. For '66 to '75, the difference is 1/4" or so. While that might not be much, it might make all the difference between a hit and a miss.
The rear backing plates won't have the same bolt pattern or hole size. They're designed for the big-bearing rear ends and you have a small bearing theoretically since you have the small brakes. Which means they may not even fit, but they probably can be made to work. I just don't know about that. If they don't fit, you would have to replace your small bearings with big bearing ends. Then the axles would have to change for sure.
The bolt hole sizes are likely different for the backing plate, but that's probably not an insurmountable issue compared to all the rest.

Paul
'71 Bronco - 302 4v
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Cstrom
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Post by Cstrom » Fri Dec 30, 2016 4:30 am

Wheel cylinders are not the same, at least on my 74 they are not. There are specific ones to the 10" brake. I ended up ordering mine because no one had them avail in town. I have a 74 with the big bearing 9" with the "small" 10" brakes. Every parts store asked if I had the 2900# rear axle or the 3300# rear axle (11" brakes). I assumed (before I researched) I had the 3300#. I was wrong :)
1974 Bronco Explorer- 302, C4,

DirtDonk
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Post by DirtDonk » Sun Jan 01, 2017 1:31 pm

Yep. You ran afoul of the whole "74-thing" too. Haha.
Whenever someone calls us up (at Wild Horses) with a '73, '74 or '75 that they want brake parts for, we prefer they actually check out their old parts first. We do finally have it down to a semi-science these days, so can get you the right ones 90% of the time, but those three years had some strange combinations of parts on the rear axles AND the steering columns. Almost a Franken-Bronco right from the factory!

Glad you got the right ones.
In the case of local auto parts stores though, for anyone reading this in the future, you need to open the box before you take the parts home too. So many times someone actually gets the right part NUMBER, only to find out that the actual parts in the box were incorrect.
Very frustrating as you can imagine.

Have fun with all your new stuff.
Oh, and since most PO's (previous owners) don't know about maintenance, then change all of your Bronco's fluids if you have not already. Including all gear oils, power steering fluid, brake fluid, trans fluid (if an automatic) and all that stuff.
And one more thing we like to tell new EB owners. When in doubt, change the rear wheel bearings.
If you know for sure they were changed at some point, or have checked them and they feel good, you should be ok. But if they have not been changed, they have a life expectancy of approximately 100k miles. If your Bronco has 120k on it, chances are pretty good that they're original unless one of the PO's was very diligent in their maintenance.
And aside from the mileage, these days after literally 42 years of living with the same old grease, most EB rear wheel bearings are pretty much dead and done. Doing the bearings while you're doing the brakes is a great time to get all those things apart and change the gear oil in the rear end too.
Just sayin....

Hopefully you're not totally done with the brakes. But hey, if you are this gives you something to look forward to in the near future.

What was that I said about "have fun" before?

Paul :mrgreen: :? :D
'71 Bronco - 302 4v
3.5" WH/Skyjacker Lift
33 x 11.50 x15 Thornbirds on 15x7 Enkei's
Kayline soft top
Hanson bumpers
Dual batteries, Large 1G alt.

WWW.WILDHORSES4X4.COM :mrgreen:

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