Rear drum brakes.

HOOK&GO · Post by **HOOK&GO** » February 23, 2010, 3:03 pm

I have done the research on the front disc conversion for a 66f100 but no body has mentioned a drum brake upgrade for the rear. Should it be nything with a 9 inch in the rear or do a donor from the same on I grab the front discs from?

Hawkrod · Post by **Hawkrod** » February 23, 2010, 3:24 pm

A rear upgrade gets discussed from time to time but it is so common that most just don't think about it. For and F100, all you need is rear brakes and axles from a 68-72 and they will fit right into your 61-67 housing or you can swap a complete 68-72 rear as it bolts right in. You need the axles because Ford changed the offset by about 3/4 of an inch in 68 so the later brakes will not just bolt onto the earlier truck. For an F250 there were changes but I think you can just bolt on the later stuff to the earlier housing (never done this one myself so I am not certain). Hawkrod

BarnieTrk · Post by **BarnieTrk** » February 23, 2010, 4:53 pm

If your rear brake system is all there and in good working order, I wouldn't suggest that you go thru all that effort.

I would, however, recommend that when you're ready for some new brake shoes, that you step up for some better-than-good quality brake shoes, new brake shoe retention spring kits for each side, have the drums turned, inspect/ensure your rear axle seals are not leaking, adjust the shoes so they you can just hear them touch when you spin the wheel, bleed the old stale fluid out of all four wheel cylinders and then check/re-adjust the shoe adjustment every couple of months or so (recall that they don't self-adjust so you need to do that periodically; depending on the amount of driving you do) and I'd dare say that the stock-sized shoes and drums will serve you just fine.

My '65 F100 (with a 9" rear end) has hauled & pulled cars, tractors, etc. with the stock brakes and they've never worried me........they've done me well.

Just my

,,, BarnieTrk

fmartin_gila · Post by **fmartin_gila** » February 24, 2010, 8:00 am

When I did the Disk install on my 62, I also got the later hardware kits for the rears which included the self-adjuster setup.. Once you get it all installed, it is just one less thing you have to remember to do.

Fred

loosrp · Post by **loosrp** » February 24, 2010, 8:56 am

I'm using this kit from Speedway,

[/url]http://www.speedwaymotors.com/9-Inch-Fo ... 6.html[url][/url]

BarnieTrk · Post by **BarnieTrk** » February 24, 2010, 9:06 am

loosrp wrote:I'm using this kit from Speedway,

[/url]http://www.speedwaymotors.com/9-Inch-Fo ... 6.html[url][/url]

Loosrp,
HOW ARE YOU MAKING THEM WORK?

The rotors in that kit are drilled for 4.5" (Ford car) and 4.75" (GM) 5-lug bolt circle patterns.
Our F-100 Slicks are 5.5" 5-lug bolt circle patterns.....

I don't think there is ample meat left on the rotor to drill in another set of lug holes.....

BarnieTrk

loosrp · Post by **loosrp** » February 24, 2010, 9:07 pm

You have to either get car axles or have your origonal axles machined to fit the rotors, it's done all the time, places like Moser Engineering, and reputable machine shops that specialize in racing/performance work will do this for you. Im changing the bolt circle to the 5-4.5 pattern, the axle flange od also needs to be cut down to less than 6.25" The machinist at work is doing mine as we speak.
Russ

Uncle Skip · Post by **Uncle Skip** » February 24, 2010, 9:14 pm

H&G.
If you're doing disk brakes in the front, there is NO reason to upgrade the rears.
You need a proportioning valve to reduce the pressure to the rear in the base case.
Bigger brakes in the rear cause a very unstable and undesirable condition known as "swapping ends".
Not only raise your blood pressure to epic heights, but it will embarrass you in public when it happens.
Rebuild what you have and be a happy camper.
U@ss