Best rear disc kit for the money using the BB 76-77 9 inch rearend

[jamesroney]

And one more for me - ease of maintenance.

Todd Z.

OK, but you have to admit that you are giving up one type of maintenance for another. And I don't like to trivialize the upgrade. Too many "bolt on" conversions snowball.

Explorer Discs in a Currie housing are NOT simple. They are a giant PITA when you have to service them. It's only "simple" when someone else does the work. But fishing the SET-20 outer seal into the housing while supporting the caliper mount while manipulating the axle retainer is NOT trivial, and trying to get the nuts started is near impossible. about 1/2 the time you end up with a leak. I have found that setting the axle on its side and letting gravity do the work is much preferred. PLUS you have to move the shock mount for caliper clearance.

I think we often forget that we ALL ordered new axle shafts when we did our conversions. Because the explorer hats don't fit over the factory 28 spline axles. And the spacer rings only work with the SET-20 bearings...which we all upgraded to when we did the conversion.

I would rather service 5 sets of drum brakes on the trail rather than 1 Explorer disc axle. I'm not exaggerating. The original Explorer is looking for a c-clip axle, so it's super easy to work on, and you don't have to deal with a retainer. The TJ uses the exact same brakes, but the shaft flanges are 5x4.5, and there room to work.

So when I build my own rear ends, I always start with Big Bearing Torino ends, New upgraded shafts, one piece (2nd gen) retainers. (Currie sells those too...different part number than the ring) Of course by then, you are looking at 31 spline shafts, so you need a 31 spline carrier. By now you've spent over $2k for your cheap disc conversion. And if I'm buying 31 spline chromo axles, I'm paying the incremental amount for 35 spline. Which means a new 3rd member.

I'm NOT trying to talk anyone out of doing the swap. I did the swap. I like the swap. I run the swap. But I don't want a casual early Bronco owner to stumble onto this thread and think they are going to go to the junk yard, and get an Explorer disc swap for $50.

 

[toddz69]

OK, but you have to admit that you are giving up one type of maintenance for another. And I don't like to trivialize the upgrade. Too many "bolt on" conversions snowball.

Explorer Discs in a Currie housing are NOT simple. They are a giant PITA when you have to service them. It's only "simple" when someone else does the work. But fishing the SET-20 outer seal into the housing while supporting the caliper mount while manipulating the axle retainer is NOT trivial, and trying to get the nuts started is near impossible. about 1/2 the time you end up with a leak. I have found that setting the axle on its side and letting gravity do the work is much preferred. PLUS you have to move the shock mount for caliper clearance.

I think we often forget that we ALL ordered new axle shafts when we did our conversions. Because the explorer hats don't fit over the factory 28 spline axles. And the spacer rings only work with the SET-20 bearings...which we all upgraded to when we did the conversion.

I would rather service 5 sets of drum brakes on the trail rather than 1 Explorer disc axle. I'm not exaggerating. The original Explorer is looking for a c-clip axle, so it's super easy to work on, and you don't have to deal with a retainer. The TJ uses the exact same brakes, but the shaft flanges are 5x4.5, and there room to work.

So when I build my own rear ends, I always start with Big Bearing Torino ends, New upgraded shafts, one piece (2nd gen) retainers. (Currie sells those too...different part number than the ring) Of course by then, you are looking at 31 spline shafts, so you need a 31 spline carrier. By now you've spent over $2k for your cheap disc conversion. And if I'm buying 31 spline chromo axles, I'm paying the incremental amount for 35 spline. Which means a new 3rd member.

I'm NOT trying to talk anyone out of doing the swap. I did the swap. I like the swap. I run the swap. But I don't want a casual early Bronco owner to stumble onto this thread and think they are going to go to the junk yard, and get an Explorer disc swap for $50.

All good points for sure! Which is why you, and I, and others often have to explain all the caveats and things to consider when swapping to Explorer discs on a housing that wasn't originally designed for them. I'd rather mess with drums on the trail too. I only recently swapped to one of the Currie 2nd gen retainers on the pass side on my rig and while it was easier than messing with the separate ring/retainer plate, it wasn't a quick and easy job.

I should've clarified in my original post that when I was referring to "maintenance", I was talking thinking about the time to change pads/remove a rotor, etc. vs. changing shoes/messing with wheel cylinders, etc.

Todd Z.

 

[ntsqd]

FWIW my Expedition RDB conversion came in at just under $600 for everything in the brake conversion. At the time you could buy ALL of the parts from Rock Auto except for the caliper banjo bolts for about $500. Such an odd part for them to not have a listing for. Mine cost more because I had to make the spacers that moved the rotor over to where the calipers were when bolted to a Dana 60. Material for that ran about $80 or so.

The more that I read about semi-floating axles and their wheel bearings, the less inclined I am to ever build such an axle. Instead I spend a large amount of money upfront to not have to deal with those.

 

[jamesroney]

All good points for sure! Which is why you, and I, and others often have to explain all the caveats and things to consider when swapping to Explorer discs on a housing that wasn't originally designed for them. I'd rather mess with drums on the trail too. I only recently swapped to one of the Currie 2nd gen retainers on the pass side on my rig and while it was easier than messing with the separate ring/retainer plate, it wasn't a quick and easy job.

I should've clarified in my original post that when I was referring to "maintenance", I was talking thinking about the time to change pads/remove a rotor, etc. vs. changing shoes/messing with wheel cylinders, etc.

Todd Z.

I admit that I did tack weld the ring to the retainer on my last build. I wasn't going to pay Currie $70 for a fancy retainer that Wilwood sells for $10. (although I do admit that the Wilwood one is the wrong depth...) So last year, I custom machined a ring, and welded it to the Wilwood retainer. I'm think I've got 4 hours into saving fifty bucks.

 

[ntsqd]

Not even minimum wage!

 

[jamesroney]

Not even minimum wage!

BTW, are you running 8 lug out back? Do your Expedition calipers clear 15 inch wheels?

And I’ve determined my Bronco labor rate gets me about $0.10 an hour.

 

[ntsqd]

Yes to 8 lug (all around - 3/4t GM 10blt/D44 FDB's on the TTB), I believe no to clearing 15" wheels. Smallest OEM wheel for those is a 16" and I don't have an 8 lug 15" to try test-fitting. At a Ø12.125" OD rotor fitting a 15" wheel over them will depend on the exact wheel's shape. General RoT is that the wheel must be 3" larger than the rotor. With ~Ø12.5" front rotors there was no hope of fitting 15's so I went to 17's.

Oh, well, then $12.50/hr is a dramatic step up in wages!

 

[bigmuddy]

Funny, when I started this thread I thought man this topic has been chewed over a bunch and probably won't get much interest. Well glad to see the interest and some new information to chew on myself as the old brain starts to remember the old stuff I thought I forgot!

 

[lars]

OK, but you have to admit that you are giving up one type of maintenance for another. And I don't like to trivialize the upgrade. Too many "bolt on" conversions snowball.

Explorer Discs in a Currie housing are NOT simple. They are a giant PITA when you have to service them. It's only "simple" when someone else does the work. But fishing the SET-20 outer seal into the housing while supporting the caliper mount while manipulating the axle retainer is NOT trivial, and trying to get the nuts started is near impossible. about 1/2 the time you end up with a leak. I have found that setting the axle on its side and letting gravity do the work is much preferred. PLUS you have to move the shock mount for caliper clearance.

I think we often forget that we ALL ordered new axle shafts when we did our conversions. Because the explorer hats don't fit over the factory 28 spline axles. And the spacer rings only work with the SET-20 bearings...which we all upgraded to when we did the conversion.

I would rather service 5 sets of drum brakes on the trail rather than 1 Explorer disc axle. I'm not exaggerating. The original Explorer is looking for a c-clip axle, so it's super easy to work on, and you don't have to deal with a retainer. The TJ uses the exact same brakes, but the shaft flanges are 5x4.5, and there room to work.

So when I build my own rear ends, I always start with Big Bearing Torino ends, New upgraded shafts, one piece (2nd gen) retainers. (Currie sells those too...different part number than the ring) Of course by then, you are looking at 31 spline shafts, so you need a 31 spline carrier. By now you've spent over $2k for your cheap disc conversion. And if I'm buying 31 spline chromo axles, I'm paying the incremental amount for 35 spline. Which means a new 3rd member.

I'm NOT trying to talk anyone out of doing the swap. I did the swap. I like the swap. I run the swap. But I don't want a casual early Bronco owner to stumble onto this thread and think they are going to go to the junk yard, and get an Explorer disc swap for $50.

Well put. They are truly a PITA, as I was reminded of a few months ago when I pulled the axles out to finally deal with a leaky diff. I was cursing everything about the setup when I was struggling to get things put back together. I have a pair of Currie one-piece retainers waiting, which will hopefully make the job less bad the next time I have the axles out.

 

[jamesroney]

Well put. They are truly a PITA, as I was reminded of a few months ago when I pulled the axles out to finally deal with a leaky diff. I was cursing everything about the setup when I was struggling to get things put back together. I have a pair of Currie one-piece retainers waiting, which will hopefully make the job less bad the next time I have the axles out.

So don't hate me, but i think the next one I build I'm going to go ahead and build the housing 2 inches narrow, and build it with the smaller 5x4.5 TJ flanges. Then just add billet wheel adapters to get me to 5x4.5. I'm even tempted to run SET-10 bearings like the TJ. A half inch of access on the OD of the axle flange is a mile.

Since i'm usually putting new ends on the housing...it seems like disc brake TJ outers is the way to go. It's the exact same as the Explorer...just impossible to find in a junkyard. But they do exist. They use 5 backplate bolts instead of 4. But then all parts, including rotors are off the shelf.

There's lots of JK based discs out there, and I kinda like them...but of course 17 inch wheels are then mandatory.

Well, strictly speaking, the next one I build will use the Wilwood dynalites with the internal shoe parking brake. Because I harvested them off a 9 inch and they are in my shed. But the NEXT, next one...

Actually this is also not 100% true. The next, next one will get drums. Which is the same as my first Bronco back in 1996. Which is why my very first sentence in the very first post says "The circle is now complete..."

 

[ntsqd]

I recall just how much effort Rob had to put into working on those RDB's. Don't recall what exactly he was doing, but I do remember that the axle flange was seriously in the way of doing it.

The next axle that I build from scratch won't be inexpensive. Torq MS 14bff stub spindles, Solid Axle Ind 5 x 5.5 wheel hubs, likely Expe RDB's again. No idea what axle that might be, but it'll likely be for the Wagon project and it's very unlikely to be a 9"

Mock-up of the Expedition parts, ignore the 4rnnr V6 caliper cores:

Access w/o the wheel hub in place would be easy, and removing it is pretty simple:

The Explorer parts do not clear a D60 wheel hub. Stationary bits and whirly bits both want to be in the same place and clearancing them is not an option.

 

[rcmbronc]

I have a fab 9" housing with floater spindles from Schreiner enterprises. Alot like stock car stuff. There hubs and standard discs. Then Wilwood calipers. Emergency/Parking brake have been a challenge. Right now my approach is to weld another bracket on the housing and use a Wilwood parking brake cable caliper. Have not fully installed yet. Wish there was maybe a better option.

Sorry to hi Jack

 

[bigmuddy]

I have a fab 9" housing with floater spindles from Schreiner enterprises. Alot like stock car stuff. There hubs and standard discs. Then Wilwood calipers. Emergency/Parking brake have been a challenge. Right now my approach is to weld another bracket on the housing and use a Wilwood parking brake cable caliper. Have not fully installed yet. Wish there was maybe a better option.

Sorry to hi Jack

Not a hijack just more interesting brake intel..

 

[ntsqd]

I'd consider adding a flange on the housing that the Explorer or wilwood drum p-brake caliper bracket would bolt to. Unless that cable mechanical caliper of wilwood's has improved considerably since I last saw one I don't have much faith in it's ability to function as a p-brake caliper.

 

[rcmbronc]

Not sure there is room back there for it with sway bar brackets, the spindle, housing brace and link mounts.

 

[ntsqd]

If you've got a Detroit or a spool as a rear diff and at least a 1" body lift (I understand this is needed to clear the rotor) then I'd consider an output shaft p-brake. Puts you back into a mechanical caliper.

 

[jamesroney]

If you've got a Detroit or a spool as a rear diff and at least a 1" body lift (I understand this is needed to clear the rotor) then I'd consider an output shaft p-brake. Puts you back into a mechanical caliper.

There was a driveshaft parking brake kit available for the Dana 20 from High Angle Driveline many years ago. The one I had required a new flange yoke on the output to mount the disc. The flange yoke required an flange CV. Which required spending more money at High Angle Driveline.

So the driveshaft brake sat in the shed for 5-10 years. I talked to Jesse after the Paradise Fire (2018) and asked about conversion parts to run his brake on my Atlas. He mentioned that no one ever bought the Dana 20 ones. They are no longer in the catalog. But if you call him, he might have some old stock, or he might tell you which one is closest. I think if you are running the AA heavy duty output shaft, it is a clone of the Jeep CJ Dana 300. So the index ring and hardware would be similar. You would need your own reaction arm, since Bronco is driver drop, and CJ is passenger. I'm not fond of their caliper. It's effective, but its big, and ugly. I always thought that the Wilwood spot caliper on the t-case would be more elegant. I also thought about using the Tesla spot caliper...but it's electric. And I'm hating electric right now. I need to go and fix the door handle on my Model S today. So I'm hating on Tesla electrics. But that hate will go away tomorrow.

I still might go with a motorcycle disc rotor and wilwood spot caliper in my LJ. It already has the 1350 CV flange. My Dynatrac Pro Rock 60 is 5x5.5 semi float, and it has some oddball Set20 housing end that I don't recognize. It came with Seville calipers. I'll have to do something. I bought the Wilwood Dynalite big bearing / big bolt 9 inch disc kit...but then I learned that Dynatrac doesn't use Ford ends. That will be a project for another day.

 

[ntsqd]

I'm recalling a p-brake rotor that fit up against an output yoke and used the u-bolts & nuts to secure it. In just now thinking about that it seems like that would require longer u-bolts or one of those strap conversions (Moroso?) with longer SHCS. If it weren't for the trouble of getting it blanchard ground after having it cut out, a plate rotor like that would be an easy SendCutSend/OSHcut part.

Having spent my first 20+ in 4x4's years with Toyotas and their companion flanges I really don't see ANY appeal in a yoke and u-bolts. None. So I don't see the flange as a necessary added expense, I see it as an upgrade to how the truck should have been built in the first place.

Do yourself a favor and stop buying dynalites. They're one of the flexiest calipers in the whole product line. In a small caliper my favorite is the dynapro. Especially since they used to (& may still be) offered with honest to gosh dust boots!

 

[bigmuddy]

There was a driveshaft parking brake kit available for the Dana 20 from High Angle Driveline many years ago. The one I had required a new flange yoke on the output to mount the disc. The flange yoke required an flange CV. Which required spending more money at High Angle Driveline.

So the driveshaft brake sat in the shed for 5-10 years. I talked to Jesse after the Paradise Fire (2018) and asked about conversion parts to run his brake on my Atlas. He mentioned that no one ever bought the Dana 20 ones. They are no longer in the catalog. But if you call him, he might have some old stock, or he might tell you which one is closest. I think if you are running the AA heavy duty output shaft, it is a clone of the Jeep CJ Dana 300. So the index ring and hardware would be similar. You would need your own reaction arm, since Bronco is driver drop, and CJ is passenger. I'm not fond of their caliper. It's effective, but its big, and ugly. I always thought that the Wilwood spot caliper on the t-case would be more elegant. I also thought about using the Tesla spot caliper...but it's electric. And I'm hating electric right now. I need to go and fix the door handle on my Model S today. So I'm hating on Tesla electrics. But that hate will go away tomorrow.

I still might go with a motorcycle disc rotor and wilwood spot caliper in my LJ. It already has the 1350 CV flange. My Dynatrac Pro Rock 60 is 5x5.5 semi float, and it has some oddball Set20 housing end that I don't recognize. It came with Seville calipers. I'll have to do something. I bought the Wilwood Dynalite big bearing / big bolt 9 inch disc kit...but then I learned that Dynatrac doesn't use Ford ends. That will be a project for another day.

I am using the atlas II. Any idea how much the T case parking brake shortens the rear driveline?
This might be an option for me as I need to buy or cut down my existing rear driveline.

Using an electric e-brake on the t-case unit I think would be the cats ass or bee's knee's or whatever the cool kids say these days..

 

[ntsqd]

Those that I've seen attached to the front side of the output flange, so no change in driveshaft length at all.
Usually they don't fit an EB without at least a 1" body lift because the rotor hits the floor.