Complete Brake System Overhaul

[JustEmptyEveryPocket]

87 MJ with a Ford 8.8 rear with discs.

 

While driving home today I had a rear brakeline blow out. Since there are several other problems with the brake system (load height sensor doesn't work, still have a single diaphragm booster, etc) and I no longer trust the rest of the brake lines, I will be replacing everything. Probably shouldn't have ever trusted them.

 

*Comanche purists may want to check out now*

 

Anyways, I am redoing everything while I am at it, and wanted to run my plans, parts, and ideas by everyone. I have never done a project like this, so any advice is welcome.

 

1. Gonna make my own lines using THIS as line, THIS bender, and a Harbor Freight flare tool. Will it matter what connectors I use, since I am basically replacing everything?
2.  Planning to use THIS to hang the new lines (I am expecting the plastic connectors to break as I take it apart), and put THIS over the new lines. Is the protector worth it?
3. Since I have rear disc brakes, I would like a better way to proportion things. So I want to get THIS. I also plan on putting in an old WJ booster that I have had sitting around for a few years. I have read multiple write-ups on installing the WJ booster, but if anyone has a personal favorite for the change, please link it. Also, what can I bench test to make sure it will work after all of these years of sitting on a shelf? 
4. I want stainless steel braided hoses to reach the calipers. The truck has ~2-3" of lift. Anyone have a good resource for these? Any specifics would be appreciated.
5. I also thought about using Dot 4 brake fluid. Anyone have a better recommendation?
6. Finally, the last major change is to add a parking brake.  I have played around with many combinations of ebrake cables, tensions, and in cab handles. None of them ever worked that well. I found THIS by Tom Woods. If anyone has it, let me know how the install went, how it works, etc. I think the concept is cool, and it should work really well. Somehow I will need to hook it up to my 97 center console handle. So all ideas welcome here.

 

Thanks in advance!

[Eagle]

1. Excellent choice on the cunifer brake line. It's easy to work with and more resistant to corrosion than the crap they sell at the parts chains. Some of the fittings into the front distribution block are larger than standard for the 3/16" brake line, so you may need to recycle those. Although the photo suggests that kit may include a few larger fittings, so those may do it. The Harbor Freight flare tool is junk. Buy a good one.

 

2. I would try to salvage the original brake line supports wherever possible.

 

3, The Wilwood proportioning valve is a good choice if you will be eliminating the rear height sensing valve. (Since you said it doesn't work, I assume you'll be eliminating it.)

 

4. No idea. Last I knew, braided line wasn't D.O.T. approved for street use. That may have changed.

 

5. DOT 4 has a slightly higher boiling point than DOT 3 but it's basically the same stuff, and it still attracts moisture. I ionly use DOT 5 silicone brake fluid. It's got a VERY high boiling point, and it's not hygroscopic.

 

6. Interesting. Personally, I'd spend a LOT of time fixing the factory parking brake before I would try a kludge like that, but Tom Woods is a reputable shop so ... whatever flpoats your boat.

[gogmorgo]

Unless you have a selectable locker and remember to use it, that's not a very effective parking brake, or at least it's no better than throwing an automatic trans in park. With an open diff (or one that behaves as open under no power) if you don't have adequate traction under both rear tires, the one without traction will spin backwards and the one with traction will just roll down the hill. It probably will work quite well in most contexts, and in fact it's not uncommon for medium-duty street-driven vehicles to use a similar arrangement, but it still doesn't totally prevent any of the wheels from turning.

I personally would look into installing a hydraulic handbrake before I went with a driveshaft brake, considering you're replacing the whole system anyway, but I'm also with Eagle on making the factory one work before I'd go that far. The 8.8 swap is common enough that you should be able to find a write-up on how someone made theirs work, even if it was in an XJ. 

 

I don't really have much other commentary on the rest of your plan. It seems solid enough. 

Nothing wrong with upgrading to DOT4 fluid, although the silicone DOT5 (not to be confused with DOT5.1) is much better, yeah, but it's also more expensive and you're not supposed to use it unless you've changed literally every component it touches, including the calipers which it doesn't look like you intend to change. DOT4 will be compatible with all your current used parts. But unless you like riding your brakes down longer hills the factory specced DOT3 should still be okay.  

[Eagle]

4 hours ago, gogmorgo said:

Nothing wrong with upgrading to DOT4 fluid, although the silicone DOT5 (not to be confused with DOT5.1) is much better, yeah, but it's also more expensive and you're not supposed to use it unless you've changed literally every component it touches, including the calipers which it doesn't look like you intend to change. DOT4 will be compatible with all your current used parts. But unless you like riding your brakes down longer hills the factory specced DOT3 should still be okay.  

 

IMHO that's a myth. There is no valid reason I've ever seen to support this notion. When I started using silicone, I just did a complete flush with the silicone, and bled until I was getting clean silicone at each wheel. The first one I did was my '88 Cherokee. It's now at 287,000+ miles, and I switched to silicone brake fluid at about 80,000. So I've been driving it on silicone brake fluid with mostly* the original lines and hoses for over 200,000 miles and at least 20 years.

 

* I have replaced the rear wheel cylinders on each side at least once.

[JustEmptyEveryPocket]

13 hours ago, gogmorgo said:

Unless you have a selectable locker and remember to use it, that's not a very effective parking brake, or at least it's no better than throwing an automatic trans in park. With an open diff (or one that behaves as open under no power) if you don't have adequate traction under both rear tires, the one without traction will spin backwards and the one with traction will just roll down the hill. It probably will work quite well in most contexts, and in fact it's not uncommon for medium-duty street-driven vehicles to use a similar arrangement, but it still doesn't totally prevent any of the wheels from turning.

So I have been thinking about this, and wanted to share my musings. First, the only way I have been parking my vehicles for 15+years is by leaving them in gear. This has worked on all kinds of slopes and in all kinds of weather, as well as on multiple vehicles. Note that I only own and drive manual transmissions, I absolutely HATE automatics. Second, if it works find to lock the transmission up (essentially what happens when you park it in gear) wouldn't this brake complete the same function, just with the option to leave the vehicle running? Finally, worst case scenario: the truck has an open diff, its parked on an extreme slope, and the ground is slick. In that case, it couldn't move in anything more than a circle, right? For one wheel to turn forward, the other wheel has to turn backwards. At some point it will be pointing in the direction that gravity pulls it and will stop moving since neither tire can rotate 'backwards'. Or am I missing something?

 

Still open to changes if anyone has suggestions. I'm dragging my feet in buying parts until Monday.

[Jeep Driver]

19 minutes ago, JustEmptyEveryPocket said:

Finally, worst case scenario: the truck has an open diff, its parked on an extreme slope, and the ground is slick. In that case, it couldn't move in anything more than a circle, right? For one wheel to turn forward, the other wheel has to turn backwards. At some point it will be pointing in the direction that gravity pulls it and will stop moving since neither tire can rotate 'backwards'. Or am I missing something?

 

It doesn't work like that. 

 

 

Open.........lockers.........whatever, doesn't matter, with the DS locked the only way the vehicle will move is if the pull is greater than the traction of the rear tires. 

[Jeep Driver]

You need to study some more on the TC brake. No one makes a brake for the 231 but one company.....High Angle Drive and it's crap. 

 

Here is the brake caliper, this caliper is from or for a, Cub Cadet  garden tractor-

 

 

http://www.fourwheeler.com/product-reviews/131-0212-high-angle-driveline-emergency-brake/

 

 

 

You need to get serious about your parking brake...........you need it! Figure it out. 

[gogmorgo]

I once watched a guy climb a hill as far as he could before he started spinning, put it in park, hop out to take a picture, and when he slammed his door his Blazer took off back down the hill. The driver's side wheels rolled normally, the passenger side dug themselves a small trench as they spun "forwards"... opposite the direction of the Blazer's movement. Fortunately it wasn't a big hill, just a steep one, and it skidded itself to a stop quickly enough at the bottom without hitting anyone or anything. Would a parking brake that prevented the wheels from turning have held it? Hard to say, but it did stay there while he had his foot on the brake.

I realize in 99.999% of situations where you'd ever park there's no chance of that happening, but I still find it unsettling to know the possibility is there. 

I also have a pair of manual trans Jeeps that split errand duties. My ZJ is always parked in gear with the handbrake set, even on flat, level ground. My mj's parking brake ratchet is stripped, so the brake doesn't hold. I leave it in gear and chock the tires if there's a noticeable slope. I've just heard of too many vehicles somehow (supposedly) coming out of gear all on their own and rolling away. I also will use the parking brake in an automatic to hold it on a slope rather than just the parking pawl on its own, or when loading a trailer hitched onto the truck. 

[schardein]

Here is 25' of brake line and 8' of stainless gravel guard for $40

 

https://www.ebay.com/itm/25-3-16-Copper-Nickel-Roll-with-45-fittings-8-ft-of-stainless-Gravel-Guard/262484945116?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

 

Here is the same thing as the Wilwood valve, but cheaper:

https://www.summitracing.com/parts/sum-g3906

 

Or retain your factory combination valve and use this somewhere in the rear line:

 

https://www.summitracing.com/parts/sum-g3905?rrec=true

 

I converted a K5 Blazer with a 14 bolt (1 ton) rear end to disc brakes back around 1997.  I used a Summit inline adjustable valve similar to the one above.  It lists a reduction of 57%.  I had to turn it nearly all the way down to balance the brakes, that is how much more effective the disc brakes were.

 

I think you have a good plan.  I think it's a good idea to use the gravel guard, especially on the hard lines on the rear axle.  I haven't worked with the cunifer line yet, but if it is softer than factory steel line, the gravel guard becomes even more desirable.

 

I plan to convert my XJ and MJ to dual diaphragm someday, and have 1996 XJ boosters on standby.  I've read both those and the WJ ones work.

 

My "problem" with rear disc brake conversions is they often have no parking brake, or the installation doesn't result in a functioning parking brake.  My opinion is this is hack.  You should have a functioning parking brake.  On the K5 Blazer, I used the Cadillac Eldorado calipers, back when they were very difficult to find, and very expensive if you didn't have cores (I found rusted beyond use cores in the junkyard that saved me hundreds in core charges).  But they worked.  I had custom parking brake cables made and it worked good.  Now the calipers are available new from Ruffstuff, oops, looks like they are out of stock.

 

https://www.ruffstuffspecialties.com/catalog/R2262-A.html

 

Drum brakes are a very effective parking brake.  Unless you are doing a lot of deep mud and/or water crossings (which can quickly destroy drum brakes) I think most people are better off with their stock rear drum brakes.  Those mini drum brakes inside the disc rotor don't seem to work well in my limited experience.  My 2001 Silverado 2500HD has that setup, and the parking brake sucks.  I'd be interested to hear other people's experience with there effectiveness.  It sounds like you are experiencing the same thing (I think the 8.8 uses that setup, correct?).

 

You need the flexible hose going to the caliper, to allow it to move (self adjust), but I wouldn't worry about stainless braided hose.  If there was a standard rubber hose available that fits the application, I would use that.  Probably be cheaper, and easily available as long as you keep a record of the part number.

[schardein]

10 hours ago, Jeep Driver said:

You need to study some more on the TC brake. No one makes a brake for the 231 but one company.....High Angle Drive and it's crap. 

 

Here is the brake caliper, this caliper is from or for a, Cub Cadet  garden tractor-

 

 

http://www.fourwheeler.com/product-reviews/131-0212-high-angle-driveline-emergency-brake/

 

 

 

You need to get serious about your parking brake...........you need it! Figure it out. 

I always wondered what the original application was for those assemblies.

 

Edit:  As a side note, Jeeps with the D18 transfer case used transfer case mounted parking brakes into the late 60s.

[AZJeff]

3 hours ago, schardein said:

 

Drum brakes are a very effective parking brake.  Unless you are doing a lot of deep mud and/or water crossings (which can quickly destroy drum brakes) I think most people are better off with their stock rear drum brakes.  Those mini drum brakes inside the disc rotor don't seem to work well in my limited experience.  My 2001 Silverado 2500HD has that setup, and the parking brake sucks.  I'd be interested to hear other people's experience with there effectiveness.  It sounds like you are experiencing the same thing (I think the 8.8 uses that setup, correct?).

The ZJ and KJ factory drum type parking brakes work as good as any, provided they are adjusted properly and free of mud and other crap.

 

 The factory would not have installed an ineffective parking brake.  Most of the issue is people using worn out junkyard parts in their conversions, and declaring all drum parking brakes junk.

[JustEmptyEveryPocket]

3 hours ago, schardein said:

It sounds like you are experiencing the same thing (I think the 8.8 uses that setup, correct?).

That is exactly my problem. I have a parking brake right now, but it doesn't hold on any type of slope. This is after many hours of adjustment and spinning the star wheel at the "drum" part of these disc brakes. I even took the cams out and buffed and greased the pins they rotate on in case that was causing binding and inhibiting the brakes being fully applied. Nothing has made the parking brake work to such a degree that I would trust it ever. Hence I want to go with something else.

 

13 hours ago, Jeep Driver said:

You need to get serious about your parking brake...........you need it! Figure it out. 

JeepDriver: Yea, I realize I need it. That is why I am changing things around. Also why I put it as part of a question in this thread. So I am left wondering how your comment is helpful or useful? Can you give me a better option (with specifics)? Or can you enumerate why the system I am thinking of "is crap"? Having read through many threads here at ComancheClub I have come across many of your comments. Often times I agree with them, especially the 'buy the correct item, buy the correct install tools, and the cost be damned' thoughts you have. However your comments of "thats stupid" or "its crap" or "forget it, I'm done" do nothing to further a thread. So if you see a better option or have a better idea, please share it. Keep your irrelevant or unsubstantiated negative comments to yourself.

[Jeep Driver]

31 minutes ago, JustEmptyEveryPocket said:

Keep your irrelevant or unsubstantiated negative comments to yourself.

 

It's not my job to convince anyone of anything. You'll have to do your own homework to determine what is obvious and true. 

 

Even if you bought some 'kit'.....

You'll have to devise your own handbrake and cable system as it is mechanical. 

Secondly, you'll either need to use a CV driveshaft as shown with 4 bolt flange similar to your front DS or you will need a flange adapter, either way you'll need a new drive shaft. 

Thirdly, as shown that POS has to be a rattle trap.........has to be. Rattles on a garden tractor it will surely rattle on your TC. 

Any way you look at it that 'kit' will cost you more than $1000

 

There are electric actuated parking brakes...............want to spend some money, look there. 

 

I'm not familiar with 8.8 brakes.......don't care to be familiar, don't want an 8.8 of any kind for any reason......that said-

Look to 9" Ford brake brackets, see below, this is the direction I want to go- I want hydraulic, locking hand brake, also an active hand brake-

What I'm doing is well beyond the scope of your question and I don't always feel like explaining myself. 

 

 

 

 

[Jeep Driver]

In the interim this is where I have gone. One question I had for the Wilwood rep was regarding the parking brake, Wilwood assured me that the brake will hold the truck in a static position as long as the brake is applied. 

I've yet to mount, we'll see. 

 

[Jeep Driver]

Something else to consider-

 

[Jeep Driver]

If you are willing to have your own mounting brackets made.......the world is your onion-

 

[Jeep Driver]

 

[Jeep Driver]

FWIW, these are the Cub Cadet brakes-

[JustEmptyEveryPocket]

JeepDriver:

Thanks for the information. That is useful. I thought about doing a second caliper (pretty common set-up on Mustang version 8.8), but I don't have a welder for fabrication. That would make brackets kind of hard to do. I may look at that option again.

[Jeep Driver]

54 minutes ago, JustEmptyEveryPocket said:

JeepDriver:

Thanks for the information. That is useful. I thought about doing a second caliper (pretty common set-up on Mustang version 8.8), but I don't have a welder for fabrication. That would make brackets kind of hard to do. I may look at that option again.

I completely forgot about Mustang 8.8 and the drifter guys with dual caliper.

For you it's a bolt-on proposition............doesn't get easier or cheaper than that. 

 

 

https://driftamerican.com/dual-caliper-brackets-79-04-mustang-with-cobra-brakes/

[JustEmptyEveryPocket]

29 minutes ago, Jeep Driver said:

For you it's a bolt-on proposition............doesn't get easier or cheaper than that. 

I'll call some places tomorrow. From previous research I think the Mustang 8.8 is smaller than the Explorer 8.8. So it won't be a direct fit. Maybe all it takes is enlarging the center hole. I'll keep looking at it.

[Jeep Driver]

 

[JustEmptyEveryPocket]

So I finally have closure on most of this post. Figured I should come back and update for anyone else that wants info like this:

 

WJ booster install went fine. I didn't get the grind right on the booster rod, but I had a second option.

 

The Wilwood adjustable proportioning valve is working as advertised. As a bonus, it has a brake light switch built in, so I have that running my brake lights instead of the pedal switch.

 

Eagle was spot on by saying 

On 8/23/2019 at 10:36 PM, Eagle said:

The Harbor Freight flare tool is junk. Buy a good one.

After three days of terrible flares, multiple different tool rentals, and one huge temper tantrum I went and bought THIS. And it is THE BEST THING EVER!! I wish I would have started there. It would have saved me so much time and frustration. Its $$$ upfront, but well worth it for this job alone, much less future applications.

 

Instead of braided stainless steel hoses, I just went back to standard rubber hoses. Seemed to work fine.

 

I did use Dot 4 fluid, only because I already had some and just bought more of the same stuff. *shrug*. No real opinions on it from me.

 

Other than the flare tool problem, this whole job wasn't terrible. I had to chase two weeping connectors, but so far I think they are fixed just by wrenching them a little tighter.

 

I have not figured out my e-brake yet. Between buying the Mastercool tool and the extra days the truck was sitting in the shop I had to get it back on the road. However, I will be taking care of that as soon as I can. I am still thinking to go with the driveshaft brake caliper and keep it a mechanical unit. The dual caliper is a really cool idea, but I don't think its the best for an ebrake. Read THIS ARTICLE for some viewpoints and opinions. If I remember I will come back after doing the driveshaft caliper brake and report back on it.

 

Thanks for the advice and info in this thread. This website is awesome.