The Stovebolt Site Forums The Shop Area Driveline Brake drums and 14 Bolt for TF?

I'm going to narrow my SWR 14 bolt axle by changing the hubs from outboard to the inboard (type B) design in order to narrow the WMS to WMS to about 62". Will this change also require different brake drums or will the original drums still work?

Original brakes will work but you have to move the mounting flange for backing plate.
There is no combination of original parts to simply bolt brakes on a single wheel 14 bolt axle with hubs from a dual wheel axle.

are you saying I can narrow my SWR 14 bolt axle using inboard hubs if I move each backing plate towards the diff by about 2"? Will I need narrower brake drums as well?

Add disc brakes to that 14 bolt, why in the world would anyone to keep those old brakes?

I'd stick with 13"x3.5" brakes, the largest brakes available. Given that shoe size there are different drums that fit them, see this post
https://www.stovebolt.com/ubbthread...-14-bolt-axle-swap-info.html#Post1249918
Not sure what size drums and shoes (and backing plate?) you have now, but probably worth getting the 13x3.5 if not already.

The shallower drums (see pictures in above link) will be the better choice, leaving more room between backing plate and leaf springs. Bendix # PDR0619, GM # 18006042, NAPA # 440-1651, is a drum with same 13x3.5" brake size but no more offset than necessary.

The difference in a Single wheel 14 bolt (from a pickup truck typically) and a cab and chassis dual wheel 14 bolt (usually a step van, RV, or service truck, no pickup bed) are the hubs used. I believe you've figured this out. Swapping the hubs from the dual wheel axle on to the single wheel housing results in a narrow enough axle for our old trucks (same as the C&C axle width)
Difficulty is the brake backing plate doesn't bolt on in the correct location on axle tube.

Your job is to correct that, more or less move the backing plate flange and weld it back on.
First figure out what brakes you want to use and measure from flange on the hub to backing plate flange on that original setup and duplicate this measurement on your axle/hub combination. Again, see notes and pictures in above link.

In my opinion the commonly used aftermarket disc brake kits for a 14 bolt are less good than the large drum brakes.. perhaps I'm wrong. Parking brake situation is also not good.

If you do want disc brakes I'd use those from a late model 3/4 or 1 ton that actually had disc brakes on the rear, and parking brake included.
See here for that info
https://www.stovebolt.com/ubbthread...-14-bolt-axle-swap-info.html#Post1249920

Grigg, which direction will I need to move the backer plates on my existing SRW axle housing (towards or away from the wheel)? I havent bought the inboard hubs yet. My original brakes are 13 x 2.5". thnks

With the 2.5” brakes my notes show you should have 4-23/32” from back of hub where drum mounts to backing plate flange.
Dual wheel type hubs on that single wheel axle results in 2-19/32”. So you move the flanges away from the wheel another 2-1/8” each side to use those brakes again.

You should investigate if the 2.5” and 3.5” brakes use same backing plate. If so you’re well on your way to having the larger brakes, if you want them. The shallower of the 13x3.5” drums uses essentially same measurement (as 2.5” brakes) from back of hub to backing plate flange, 4-11/16”. This 1/32” variation could be acceptable in manufacturing, I’ve only had a few axles to measure, not enough of the same to compare.

Also, take your own measurements and do your own calculations in case your situation is different or I messed mine up.

Thanks again Grigg. I'm starting to consider just looking for a C&C 14 bolt rear end.

How wide are your springs center to center? 41.5"?
If so then the C&C axle with the 13x3.5" brakes they come with leave very little room between backing plate and your springs, difficult to bleed the brakes.
One solution to that is use those shallower drums and move the backing plate flanges toward the wheel 1.25" each side, or make a spacer to do same.
Again, https://www.stovebolt.com/ubbthread...-14-bolt-axle-swap-info.html#Post1249918

If you do the above it's not much more or less work that swapping hubs on a single wheel 14 bolt and also correcting backing plate location.

Yes they are 41.5" center to center. I understand your points. 2 questions: a. How about use of a 90 degree fitting with the bleeder? b. Do you know where I could buy the weld-on backer flange plates? Thanks!

It’s really just wrench clearance for bleading and installing brake line too that is difficult, possible I believe but difficult.
It’ll also look a little better with the shallower drums.

I don’t know of any aftermarket flanges. You could harvest used ones or make new. Welding them on square to the axle will take a little care.

Thanks I'd appreciate it.

By any chance, are the inboard hubs on the original Task Force HO52 axle compatible with a 14 bolt axle?

Yes kind of. I think with changing out a bearing they can be made to fit.
The resulting axle width is not useful, at least didn’t seem useful to me when looking into it, I forgot the measurement. Also brakes don’t bolt on, still need to move backing plate flange.
Newer hubs allow using newer brakes, easier to get parts for longer into the future.

Thanks for the info Grigg.

Grigg,

I purchased two inboard hubs for my SRW 14 bolt axle and plan on keeping the shallower 13" brake drums. I realize I need to move the brake mounting flanges inward about 2" or so. Will I be able to mount my brake drum on the outer part of the hub to facilitate easier brake work in the future? I see the lug bolt splines don't fit all the way into the hub. Again my goal is to have 62.5 WMS to WMS

Thanks

Some drums may fit outside the hub even though intended for inside, some may not. They need to fit snug on the hub and not have brake parts interfere with the hub.

Axle width will be wider with drums outside the hub, likely not an issue.

For a dual wheel truck the wheels are hub centered, installing drums where wheels go means no more hub pilot left for the wheels.
Single wheel trucks are stud centered, so OK to use pilot on hub for the drum and lugs still center the wheel .

I’ve considered it before but decided not to go that way, I’d keep drums where they were intended on the hub.

ok n thanks again