Rear disc brakes on a TJ?

What about the parking brake? Is it easier to lock up the rear tires using the parking brake with rear disk?
If they’re both setup properly the parking brake will lock up with either of the setups, not that you want to do that (quick way to end up in a ditch backwards or upside down). The problem with the stock full drum setup is that they regularly stop adjusting properly, so the shoes wear down slightly, then don’t adjust outwards like they’re supposed to, then the service brake wheel cylinder or the parking brake cable can’t pull the shoes out enough of a useful amount to get much grab out of them. This is why I can not fathom why so many people recommend keeping the drums. The discs are better in every way simply due to the drum in hat doing the parking brake job (and never really goes out of adjust) and then has a constantly extending caliper for the braking portion, which yes due to the combo valve, is not much brake at all (as it should be).

My guess on why so many recommend keeping the drums when a drum vs disc swap comes up, is probably due to those saying to do so already having disc and not really knowing how frustrating the drums can become. That or they don’t realize how bad their own drums are. You immediately lose pedal feel and gain a bunch of pedal travel when the drums stop adjusting and the shoes wear to the point where they have to actually move to hit the drum.
 
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To put the rear disc braking (or lack thereof) into perspective, mine don’t even stall the engine (manual trans when idling in 2WD on jack stands). It bogs way down like it’s going to die, but doesn’t. 4.10 and 31’s. Take that and imagine that same minimal force out on the road, and the rears are clearly barely doing anything, even in disc form.
 
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To put the rear disc braking (or lack thereof) into perspective, mine don’t even stall the engine (manual trans when idling in 2WD on jack stands). It bogs way down like it’s going to die, but doesn’t. 4.10 and 31,s
Pull away from stop with your hand brake fully on, if it dont stall brakes need adjusting or renewing.
Its not that long ago every vehicle had drum brakes all round :)
Its the front that stops you most that's why vehicles these days have front disks but rear are not necessary they are cheaper to produce and work with ABS.
With a manual I presume its expected you know how to engine brake via down shifting to save brake maintenance. drum brakes are better for parking as they lock better when parked.
If its for performance in certain use situations then I suppose its worth a swap to all disk.
 
Pull away from stop with your hand brake fully on, if it dont stall brakes need adjusting or renewing.
Its not that long ago every vehicle had drum brakes all round :)
Its the front that stops you most that's why vehicles these days have front disks but rear are not necessary they are cheaper to produce and work with ABS.
With a manual I presume its expected you know how to engine brake via down shifting to save brake maintenance. drum brakes are better for parking as they lock better when parked.
If its for performance in certain use situations then I suppose its worth a swap to all disk.
You missed what I was saying. The parking brake will absolutely stall the engine even if I give it gas. I was talking about slamming the brake pedal while idling in gear on jack stands, the rear disc calipers do not grab the discs hard enough to stall the engine in 1st gear. That is to illustrate how little work they are supposed to do and that is intentional from Jeep.

I would never downshift to save my brakes. That’s the whole purpose of brakes, is to stop the vehicle. Black magic brakes make it so easy to stop, why would I use my clutch for that? I’m not driving a semi.

the performance of the drum-in-hat setup with disc brakes has far outperformed the parking brake on the stock drum setup in my experience. That is because of the separation of duties and I know I am not the only one experiencing the same results.

The discs are better in every way.
 
You missed what I was saying. The parking brake will absolutely stall the engine even if I give it gas. I was talking about slamming the brake pedal, the rear disc calipers do not grab the discs hard enough to stall the engine in 1st gear. That is to illustrate how little work they are supposed to do and that is intentional from Jeep.

I would never downshift to save my brakes. That’s the whole purpose of brakes, is to stop the vehicle. Black magic brakes make it so easy to stop, why would I use my clutch for that? I’m not driving a semi.

the performance of the drum-in-hat setup with disc brakes has far outperformed the parking brake on the stock drum setup in my experience. That is because of the separation of duties and I know I am not the only one experiencing the same results.

The discs are better in every way.
You would never down shift to save brakes? lol you need to stick to an Automatic lol
 
You would never down shift to save brakes? lol you need to stick to an Automatic lol
As I said, I’m not driving a semi. I’m also not in the mountains. I also prefer my brake lights light up when I’m slowing down. I also see no reason to use my clutch more when I have cheap, easily replaceable brakes that are literally only designed to do that one job.
 
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As I said, I’m not driving a semi. I’m also not in the mountains. I also prefer my brake lights light up when I’m slowing down. I also see no reason to use my clutch more when I have cheap, easily replaceable brakes that are literally only designed to do that one job.
Didnt learn to drive in a stick shift I see :) Nothing wrong with that but if you had learned in a manual and driven mostly manual all your life you may understand where I am coming from! Hardy Ferodo loves it. :)
 
To put the rear disc braking (or lack thereof) into perspective, mine don’t even stall the engine (manual trans when idling in 2WD on jack stands). It bogs way down like it’s going to die, but doesn’t. 4.10 and 31’s. Take that and imagine that same minimal force out on the road, and the rears are clearly barely doing anything, even in disc form.
I can fix that, not that you should but I can. ;)
 
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I can fix that, not that you should but I can. ;)
is that not normal behavior? Or is it, hence why you said “not that you should”?

Curious what you would change, if anything? Seems to be a fully bled system, stock booster/master and stock combo valve.
 
Pull away from stop with your hand brake fully on, if it dont stall brakes need adjusting or renewing.
Good way to break the anchor off the backing plate on drum and discs. Don't do that.
With a manual I presume its expected you know how to engine brake via down shifting to save brake maintenance.
Yep, that's the way I do it because it is so much easier and cheaper to replace a clutch.
drum brakes are better for parking as they lock better when parked.
Not true at all. They are equivalent in one direction but not the other due to the primary/secondary shoe arrangement of our servo drum brakes. They work much better in reverse than they do in forward. Disc parking brakes work the same both directions because they have the same shoe size and are not servo style.
If its for performance in certain use situations then I suppose its worth a swap to all disk.
There is not a measurable performance difference where it matters between the two.
 
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Never been a fan of drum brakes, wondered what folks views are on a retrofit of a rear disc upgrade on a 4 litre auto?
I installed a kit from Crown. It's essentially all ZJ components. I'm happy with it, I certainly don't miss the drum maintenance.
 
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Good way to break the anchor off the backing plate on drum and discs. Don't do that.

Yep, that's the way I do it because it is so much easier and cheaper to replace a clutch.

Not true at all. They are equivalent in one direction but not the other due to the primary/secondary shoe arrangement of our servo drum brakes. They work much better in reverse than they do in forward. Disc parking brakes work the same both directions because they have the same shoe size and are not servo style.

There is not a measurable performance difference where it matters between the two.
I wasnt really suggesting he do that! but he said it doesn't stall in gear on axil stands when the park brake is pulled on :)
 
Never been a fan of drum brakes, wondered what folks views are on a retrofit of a rear disc upgrade on a 4 litre auto?
I have rear disc brakes. It’s easier to service disk brakes. Love
 
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