Rear Disc Brake Conversion With Parking Brake

I am feeling a bit overwhelmed with all the new info....Let me see if I got this straight:
1) Using the GM K10 style 'large' brackets and calipers, you would also use the 'thick' CJ rotors. It seems very straightforward, but doesn't have option for a rear mechanical ebrake integrated into the service caliper (as they were front D44 in the original application) - so that means a second smaller parking brake caliper (like the Willwood ones Kyle and John show). To ensure I understand, If going this route, you have fab some sort of parking brake caliper bracket that attaches to the service caliper bracket? In theory, for the same reasons John and Kyle probably suggest, I like this route - not sure if I can fab the required additional parking brake caliper bracket.
2) There is a second option to use a 'small' GM style set-up - I am much less familiar with this, but it appears its something like S10 caliper brackets wtih Eldorado style calipers? Not sure which rotor would go with this - the 'thin' CJ style? Advantage of this set-up would be getting Eldorado rear calipers that have the integrated parking brake cable. Looks like Richard at R&P and Jeepsterman are using these Eldorado style calipers. Maybe I should give Richard a call next week about his brackets....

I think I got that straight - but let me know if I don't.

 

I think its mostly all the plastic connections - those caps with the sort of hose clamp that go on top of the MC directly as well as the plastic reservoir 'bottles' that always seem to drip where they are clamped into the basal mount thing. I have them remote mounted on the fenderwell - originally they were on the firewall but I moved the battery there. I think I'd prefer a more traditional MC with built in reservoirs (all metal, no plastic), even if its a bit difficult to check fluid level. Also, the willwood cylinder has the brake line ports on the bottom - I guess this give a bit more clearance along the inside for stuff like exhaust etc, but I am not skilled enough to bend brake lines tight enough on the underside without them hanging down a bit exposed below the frame rail. At one time I was looking for some 90 degree angle fittings to use at the MC port to keep the lines up tighter.

 

I think I saw the pic from Ted....I think you said you didn't use the remote reservoirs - I am wondering about doing that as well and just capping the hose nipples on those 45 degree caps. In this case, its mounted in a wagon with sbc and sm465 - so hard to compare fitment/clearance with the CJ or any other set-up. I believe the wagon/PU bracket (from R&P) is different than a CJ bracket (I think), but I don't know how much that really affects things. Herm makes a bracket for the wagons as well - again, maybe the CJ and wagon brackets are similar - maybe not? My CJ came with OEM dual MC so I don't know much about how the CJ single to dual MC conversion really works. Anyway, the set-up seems fine in terms of the MC - some on OWF complain that R&Ps bracket is not rigid enough and they have added some additional metal support pieces. I can see why they say that, yet it hasn't been a concern for me and it seems to work fine (still running the OEM manual adjust 11" drums) - just the leaky reservoirs and various connections that are annoying. Too many other more immediate things needed on the 58 to be to worried about the leaky stuff right now - its also quite possible the floor pedals get replaced with hanging and move the MC (and clutch res) to the firewall.

 

I think the 'small' GM set-up (and similar in size but different design tracker/sidekick set-ups) have plenty of stopping power - especially for a cj. Honestly, its probably plenty of stopping power for a wagon or PU as well. And if going either of those routes, there is the option for rear disc parking brake - either using the Eldorado style caliper with the GM set-up, or the electric e-brake with the tracker/sidekick set-up. But something about the sort of old school 'large' GM set-up from 1/2 ton trucks seems cool on the slightly larger and heavier wagon (and hopefully built a bit bigger/taller one of these days) - especially with a sbcv8 in it. I get that you have to press the discs onto the hub lugs and thus replacing/resurfacing the rotor would be more hassle, more likelihood of knuckle clearance grinding needed, and more importantly, a more difficult parking brake (so why do I like this conversion?). I'd have to fab up some sort of attachment to the caliper bracket on the rear to mount a mechanically operated parking brake caliper - but for some reason, I don't think it would be all that hard? I haven't held the caliper bracket in hand - especially with the caliper mounted on it - but seems you could weld or bolt on (if there is clearance) a small 'extension' of metal to the bracket to mount the 2nd caliper, and those brake calipers are pretty small. Getting the spacing/positioning right in relation to the disc is certainly the hard part, but seems doable (of course, building a floor trans cover seems doable and I still haven't been able to make one for the 58 that works so I should probably be a bit hesitant). The only other aspect I might need to work out is the knuckle stud length. Its a good time to make this upgrade as well, and when replacing the drum backing plate with the caliper bracket, I think the caliper bracket is significantly thicker and longer studs would be needed than what would be used if keeping the drums.

 

I have been hesitant to go the route of the 'small' disc conversion with eldorado calipers due to a friend's difficulty with them....his disc conversion has some variables beyond what is a typical CJ type conversion, but some of his comments are:
The eldo calipers need the parking brake mechanism to function - and be routinely used - as that system is used to adjust for pad wear. If the parking brake system does not work 1) the brakes are a pain to get adjusted at installation and 2) the brake will cease to be useful as the pads wear. This is the issue I need to tend on my right rear - the pads are no longer touching the disc (disk is surface rusty).

There is an EASY bench test that can be performed at the auto parts store to see if the caliper has been assembled properly:
1) Remove the parking brake return spring
2) Rotate the parking brake arm from full off to full applied. The piston should extend out of the cylinder.
3) Rotate the parking brake arm from full applied to full off.
4a) If the piston retracts to the position it was originally at - the system is not operating as desired. Have the store send it back for another (and cross fingers).
4b) If the piston does not fully retract - that's a properly assembled caliper - one you want to use.

4a option - OR - you take the caliper home and disassemble the caliper and "adjust" it. Some of the photos (2x4 pix) get into the adjustment process. I will be doing the adjustment to the caliper / piston / parking brake assembly on mine. I wished to make a short video on these things - now is a perfect time to get it done.

Wondering if anyone else with eldo calipers has had this issue, or if its just a one off and or possibly magnified by other challenges with the system....Jim has fought his rear brake disc conversion for quite a few years - some of that is its a bit unknown/unconventional that came from the PO, and some of that has been the learning curve and frustrations of eldo calipers.

 

I should be able to go large 1/2 ton conversion with 15" aftermarket aluminum wheels - but can't go as big as the jeepsterman kit without different wheels. But, I would like to run 16 aftermarket wheels on the 58 as it would open up a better size tire....but pretty sure that is not going to happen with budget limitations. Or I could do the rims and not the brakes!

I've looked into Brennan's brackets a bit - but certainly not as much as the GM style swap. I get that he promotes that they fit the front knuckle without grinding and that if you want a more OEM style steel wheel, it gives you the chance to run them without spacers, or just a 3/8" spacer, AND the rotors are slip over for easy install/removal when needed. I can definitely see the appeal, and if I was converting a more original style cj, I'd be heading this direction. Otherwise, although I think it seems like a functional solution, I prefer to go with a more traditional (or maybe 'old school') GM conversion for my 58 project - which is already pretty GM focused. The smaller 1/4 ton conversion with eldorado calipers is really tempting given the integrated parking brake caliper, but....anyway, its been a lot of good research.

 

The parts dude website discusses that some D25/27 wheel hubs will not properly accept the GM/Jeep style rotors that need to be pressed together with the lug studs due to how the backside of the hub is formed.
You need to check the back of the wheel hub to ensure it is flat and not rounded, as it needs to lay flat on the rotor and have the pressed studs hold it together. Call me if you have questions about this. See picture.


I've not seen this mentioned anywhere else with anyone doing a GM style conversion and using later CJ style rotors (either thick or thin). Would this explain some of the issues with clearance some have had....I think in fockers detailed thread there was some discussion of using a different wheel bearing race if the rotor rubbed against the caliper bracket - wondering if this might be the cause?


And finally, this has to be one of the coolest jeeps I've seen....very nice c101! like that wheelbase...

 

So if using a later disk hub (which I assume is the same as a later CJ hub from a D30 disk set-up) on a non-modified D25/27 drum axle, you would use the OEM replacement D25/27 wheel bearings and races. The same hub could be also used on a D30, but would need different wheel bearing/races.

not disagreeing at all....but the cost of disc conversions, even when piecing it together yourself keeps going up....those 11" self adjusting backing plates are looking better and better, and I bet I know someone who is about to get rid of their D18 drum brake cap since they don't have a drum for it anymore, so at least I'll have a placebo parking brake.