Rear disc brake conversion - Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 04-28-2010, 12:58 PM   #1
Jeeper
 
adkjoe's Avatar
 
Join Date: Aug 2009
Location: Northern Vermont
Posts: 1,618
Rear disc brake conversion

So while my funds are building back up I need a cheap Jeep project. I'm thinking of doing this
D35 Disc Brake Conversion - 1

Seems pretty straight forward, theirs plenty of grand Cherokees in the yards around. Besides a 1996 does anyone know any other years I can use? I would imagine I could use any grand Cherokee with a D35c right? Has anyone done or attempted this mod? any advice?

Also, when taking the backing plate off of the donor Cherokee I need to remove the c- clips and pop out the axles to get it off correct?
__________________
Vermont
Anyone who can legally own a firearm can carry it concealed in Vermont with no permit/license
of any kind
adkjoe is offline   Quote
Old 04-28-2010, 01:27 PM   #2
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 40,743
Yep the axle shafts have to come out to get the backing plate off.

If you're wanting to do a rear disk brake conversion to make brake maintenance easier, go for it. If you're wanting to do it for better braking, save your $$$.

Converting rear drum brakes that are working properly to disk brakes won't improve your braking performance or make you stop any faster. I did the rear drum to disk conversion on my TJ years ago when I had more $$$ than experience with rear brakes and was bummed that there was absolutely no discernable improvement in braking afterwards. I knew there wouldn't be much, if any at all since the rear brakes only provide 20% max of the total braking, but I was hoping there might have been... nope.

__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 04-28-2010, 01:34 PM   #3
Jeeper
 
adkjoe's Avatar
 
Join Date: Aug 2009
Location: Northern Vermont
Posts: 1,618
Yea I'm mainly doing it for easier maintenance, Drum brakes piss me off

Shouldn't cost me much as long as I can find caliper in good shape. I will put a fresh pair of rotors and pads on but use the junkyard calipers and backing plate. I know the axles have to come out to get the drum plate off but they also has to come out to get the plate off of the disc brakes on the Cherokee?

Is this something you would do again Jerry even knowing it didn't improve braking?
__________________
Vermont
Anyone who can legally own a firearm can carry it concealed in Vermont with no permit/license
of any kind
adkjoe is offline   Quote
Old 04-28-2010, 01:44 PM   #4
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 40,743
I wouldn't do it again. Rear brakes do so little work that they don't wear out quickly enough for me to worry about the slight extra work to replace drum brake shoes & adjust them.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 04-28-2010, 03:19 PM   #5
Jeeper
 
daanbc's Avatar
 
Join Date: Mar 2009
Location: Palm Beach Fl.
Posts: 815
Quote:
Originally Posted by Jerry Bransford View Post
I wouldn't do it again. Rear brakes do so little work that they don't wear out quickly enough for me to worry about the slight extra work to replace drum brake shoes & adjust them.
Jerry, would you reccomend someone to convert to rear disk's if they tow every now and then? Would it make a difference at all? I will be switching out the tranny fluid with synthetic next week. I hear the synthetic has a higher burn rate then reg. tranny fluid. For that bit of $$ I'd like to play it safe then sorry later. Even though I don't tow alot, when I do I want to make sure I do it the best way possible. (with a jeep) that is. LOL.
daanbc is offline   Quote
Old 04-28-2010, 03:43 PM   #6
Jeeper
 
chop110's Avatar
 
Join Date: Apr 2010
Location: TX
Posts: 455
Just to chime in, Jerry is right. I converted my rear from drum to disc three years ago and have not really noticed any difference in braking power (I felt like a sucker). I have recently looked at my rear pads and they still have a ways to go before replacing.

If anyone else is interested in more braking power, I've heard good things from double piston kit from VANCO. Although at $750 a pop, it is really pricey.

VANCO Power Brake Systems Wrangler/Commanche/Grand Cherokee/Cherokee front brake upgrade kit Reviews, Ratings, Specs & Prices
chop110 is offline   Quote
Old 04-28-2010, 03:50 PM   #7
Jeeper
 
adkjoe's Avatar
 
Join Date: Aug 2009
Location: Northern Vermont
Posts: 1,618
Well it seems like a pretty easy project and I can get the parts cheap from the junkyard and I need something to do. I've been procrastinating taking off my fenders and painting so this will keep me busy while I procrastinate some more...I just hate drum brakes and want them gone, I don't really care about weather it will brake better or not but I thought for sure it would so thanks for the heads up guys i'm surprised.
__________________
Vermont
Anyone who can legally own a firearm can carry it concealed in Vermont with no permit/license
of any kind
adkjoe is offline   Quote
Old 04-28-2010, 03:58 PM   #8
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 40,743
Quote:
Originally Posted by daanbc View Post
Jerry, would you reccomend someone to convert to rear disk's if they tow every now and then? Would it make a difference at all? I will be switching out the tranny fluid with synthetic next week. I hear the synthetic has a higher burn rate then reg. tranny fluid. For that bit of $$ I'd like to play it safe then sorry later. Even though I don't tow alot, when I do I want to make sure I do it the best way possible. (with a jeep) that is. LOL.
If your trailer is heavy enough to where you're worried about that, then the trailer should already have brakes on it. But even so, the rear brakes provide such a low percentage of the overall braking, 20% of so from the rear and 80% from the front, that rear drums are still fine even for towing.

And yes, synthetic ATF can withstand higher transmission temps than conventional ATF can before it is damaged.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 06-10-2010, 08:24 PM   #9
Jeeper
 
EdJonesJeeper's Avatar
 
Join Date: Jan 2010
Location: Western NC
Posts: 1,008
I'm sitting on a tj d44 in my garage for 4 more weeks and was thinking about it.
I've done drum brakes and they were difficult but not impossible to do in your driveway. And I'm no mechanic.

You might have convinced me to save my $$$. Although I could tell the differance when I had my 318 ZJ on 31's with 2"BB.

How thought how could you FORCE the rears to pull more than 20% of the weight?
Seems like you could set up some sort of valve/ballast.

I've always wanted an emergency break that pulled the disk instead of the drum inside the disk. Drifters have something similar. I think that would be sick in the Jeep!!!!... uhmm How could I do that on a budget?
__________________
99' TJ locked and beat
EdJonesJeeper is offline   Quote
Old 10-12-2015, 09:59 PM   #10
Newb
 
Join Date: Oct 2015
Posts: 1
I tried this on my 88 yj. I got a donor axle off a 96 zj thinking it was all I was gonna need. Wrong. My lack of experience reared its ugly head again lol. Lesson learned. I'm still in the process of working out all the bugs. Just thought I'd post this for anyone thinking about doing this to their Dana35 with BOLT ON axles.
Rmga420 is offline   Quote
Old 10-13-2015, 05:58 AM   #11
Supporting Member

WF Supporting Member
 
TJ4Jim's Avatar
 
Join Date: Feb 2012
Location: Long Branch NJ
Posts: 2,415
I would do it again just to have an E-brake that works the same every time I use it.
__________________
1999 Wrangler Chili Pepper Red

If you come to a fork in the road take it.
TJ4Jim is offline   Quote
Old 10-13-2015, 06:21 AM   #12
Jeeper
 
Join Date: Apr 2013
Posts: 6,499
Most TJ rear disc setups use a mini rear drum for ebrake/park brake only

The original owner of mine set it up as a to be towed vehicle with full size warn manual hubs on all four wheels and a warn full floater kit on rear D44

That kit used a Cadillac Eldorado rear brake caliper and a CJ rotor. That caliper has a built in park brake no drum involved

After a little change in length of lever below hand brake cable (bolted on about one inch extension$ to increase cable travel) I now have excellent parking brake on my 98 sport that is not directional biased like the stock mini drum on my wife's 04 rubi

Plus Rivera's and Toranado's and Eldorado's are plentiful at up pull it yard
Digger84 is offline   Quote
Old 02-17-2016, 07:29 AM   #13
Jeeper
 
Cole Man's Avatar
 
Join Date: Jun 2013
Location: SE P.A.
Posts: 503
Im reviving this thread because I plan or replacing my malfunctioning drums very soon. Is the parts in Stus write everything that is needed? Ive read other threads and it seems more in depth than that.
__________________
97 TJ Sport Manual, Stone White
33in KM2's, 3in Rustys Coils, Rear Coil Relocation, Upper Adj. RC CA's, JKS Disconnects, SkidRow Steering Box Skid
Cole Man is offline   Quote
Old 02-17-2016, 09:17 AM   #14
Supporting Member

WF Supporting Member
 
TJ4Jim's Avatar
 
Join Date: Feb 2012
Location: Long Branch NJ
Posts: 2,415
Quote:
Originally Posted by Cole Man View Post
Im reviving this thread because I plan or replacing my malfunctioning drums very soon. Is the parts in Stus write everything that is needed? Ive read other threads and it seems more in depth than that.
I ordered new E-brake cables and rear brake hoses for a 98' GC (donor vehicle) as if I recall Stu's site does not get into that clearly. I also welded tabs on the rear to mount the brake hoses and I modified the e-brake splitter assembly by removing one link to allow for the longer GC cables.

I would probably figure on replacing the axle seals while the axle's are out.

It works great and I have not touched the setup in almost a year, including not having to re-adjust the e-brakes.
__________________
1999 Wrangler Chili Pepper Red

If you come to a fork in the road take it.
TJ4Jim is offline   Quote
Old 02-17-2016, 09:21 AM   #15
Jeeper
 
Mattel's Avatar
 
Join Date: Jul 2015
Posts: 96
IM in the middle of a 8.8 swap.

I think you guys may be missing something.

Drum brakes require less fluid pressure to activate than Disk brakes.

The master cylinder has a proportioning valve that adjusts the pressure for the rear and the front.

in any hydraulic system, if you have the wrong pressure you will not take full advantage of the additional stopping power.

Im at the point of trying to figure this out, can we put our heads together and look at this issue for a bit?
__________________
Luck Favors the Prepared
Mattel is offline   Quote
Old 02-17-2016, 09:24 AM   #16
Jeeper
 
Cole Man's Avatar
 
Join Date: Jun 2013
Location: SE P.A.
Posts: 503
Ive read the proportioning valve is the same for TJs drums or discs.
__________________
97 TJ Sport Manual, Stone White
33in KM2's, 3in Rustys Coils, Rear Coil Relocation, Upper Adj. RC CA's, JKS Disconnects, SkidRow Steering Box Skid
Cole Man is offline   Quote
Old 02-17-2016, 10:41 AM   #17
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 40,743
Quote:
Originally Posted by Cole Man View Post
Ive read the proportioning valve is the same for TJs drums or discs.
What you read is correct.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 02-17-2016, 11:34 AM   #18
Jeeper
 
Cole Man's Avatar
 
Join Date: Jun 2013
Location: SE P.A.
Posts: 503
So it really is bolt on? I just have to see how the rubber lines connect to the tj hard lines and figure out the e brake cabel
__________________
97 TJ Sport Manual, Stone White
33in KM2's, 3in Rustys Coils, Rear Coil Relocation, Upper Adj. RC CA's, JKS Disconnects, SkidRow Steering Box Skid
Cole Man is offline   Quote
Old 02-17-2016, 12:32 PM   #19
Jeeper
 
Big Bad John's Avatar
 
Join Date: Sep 2015
Location: Dallas TX
Posts: 167
Wow I'm really surprised that there would be no difference in stopping power noticeable. My old Cherokee had drums in the rear just like my TJ does, and every time those brakes got wet they pretty much ceased to work, although they never worked that well to begin with. I also constantly had to tighten the emergency brake cables. I'm having the same problem with my e-brake now, but the TJ's a 5 speed so I have no "park" gear to leave it in. The only way I can stop from rolling is leave it in reverse.... Maybe I'll just rebuild the drums and save the cash for something else.
__________________
Whether something is a success or failure is partially a matter of perspective. If you still have most of your fingers and/or toes, at least one eyebrow and are still above ground - well you'r not doing too bad!
Big Bad John is offline   Quote
Old 02-17-2016, 12:41 PM   #20
Jeeper
 
freeskier's Avatar
 
Join Date: Mar 2011
Location: Longmont, CO
Posts: 2,827
Quote:
Originally Posted by Cole Man View Post
So it really is bolt on? I just have to see how the rubber lines connect to the tj hard lines and figure out the e brake cabel
There's nothing special about the brake lines, it's all just standard stuff for 3/16" hard lines.

For e-brake just buy cables for a Rubicon.
__________________
CU Boulder Aerospace Engineering
freeskier is offline   Quote
Old 02-17-2016, 12:58 PM   #21
Jeeper
 
Cole Man's Avatar
 
Join Date: Jun 2013
Location: SE P.A.
Posts: 503
Ok Im just pretty unfamiliar with brakes and brake lines in general. I wasnt sure if Id have to "flare" a line or anything or if it would just screw together or what honestly.
__________________
97 TJ Sport Manual, Stone White
33in KM2's, 3in Rustys Coils, Rear Coil Relocation, Upper Adj. RC CA's, JKS Disconnects, SkidRow Steering Box Skid
Cole Man is offline   Quote
Old 02-17-2016, 02:16 PM   #22
Jeeper
 
YJeff's Avatar
 
Join Date: Dec 2010
Location: Menifee, Ca
Posts: 82
I just finished the d-35 with drums to a D-44 with discs.
Unfortunately there was no improvement in braking at all
YJeff is offline   Quote
Old 02-17-2016, 02:40 PM   #23
Jeeper
 
Cole Man's Avatar
 
Join Date: Jun 2013
Location: SE P.A.
Posts: 503
Im not expecting gains in stoppimg power rather just looking for easy maintenance and reliability.
__________________
97 TJ Sport Manual, Stone White
33in KM2's, 3in Rustys Coils, Rear Coil Relocation, Upper Adj. RC CA's, JKS Disconnects, SkidRow Steering Box Skid
Cole Man is offline   Quote
Old 02-17-2016, 02:46 PM   #24
Supporting Member

WF Supporting Member
 
TJ4Jim's Avatar
 
Join Date: Feb 2012
Location: Long Branch NJ
Posts: 2,415
Quote:
Originally Posted by Cole Man View Post
Ok Im just pretty unfamiliar with brakes and brake lines in general. I wasnt sure if Id have to "flare" a line or anything or if it would just screw together or what honestly.
I did not see how it could be accomplished without performing new flairs into each of the brake hoses. Each of the brake lines terminate at where the wheel cylinders used to be so I cut several inches off each hard line and re-flared to adapt to the hoses.
__________________
1999 Wrangler Chili Pepper Red

If you come to a fork in the road take it.
TJ4Jim is offline   Quote
Old 02-17-2016, 03:08 PM   #25
Jeeper
 
Cole Man's Avatar
 
Join Date: Jun 2013
Location: SE P.A.
Posts: 503
Well I guess Ill just have to learn then and rent the tools
__________________
97 TJ Sport Manual, Stone White
33in KM2's, 3in Rustys Coils, Rear Coil Relocation, Upper Adj. RC CA's, JKS Disconnects, SkidRow Steering Box Skid
Cole Man is offline   Quote
Old 02-17-2016, 05:08 PM   #26
Jeeper
 
freeskier's Avatar
 
Join Date: Mar 2011
Location: Longmont, CO
Posts: 2,827
Quote:
Originally Posted by Cole Man View Post
Well I guess Ill just have to learn then and rent the tools
You can also buy pre made lengths of brake line that are already flared with fittings.
__________________
CU Boulder Aerospace Engineering
freeskier is offline   Quote
Old 02-17-2016, 06:07 PM   #27
Knows a couple things...

WF Supporting Member
 
Jerry Bransford's Avatar
 
Join Date: Nov 2005
Location: Escondido, Calif.
Posts: 40,743
Quote:
Originally Posted by Cole Man View Post
Well I guess Ill just have to learn then and rent the tools
It's not hard to learn how to perform the double-flare that is required. Rent/borrow a double-flare tool and do a couple practice flares on the part of the hard line you cut off and you'll be good to go.
__________________
When you have a choice, buy American.
Jerry Bransford is offline   Quote
Old 02-18-2016, 06:48 AM   #28
Jeeper
 
Mattel's Avatar
 
Join Date: Jul 2015
Posts: 96
a flair tool is cheap! Just pick one up for $10 at hardware store. Great idea to cut and practice on old hard line.

I found instead of steel line I found harder stainless steel lines for $10 for short one and $17 for long one.

Im re-using the main line and cube splitter and just bending the new lines, if you bend your own lines you can locate them in a place that cannot be smashed or damaged during your wheeling.

Great news on the proportion valve! You just saved me research time! u guys rock!

Well, its back to the garage tonight to paint my new trusses and more research!
__________________
Luck Favors the Prepared
Mattel is offline   Quote
Old 02-18-2016, 05:49 PM   #29
Supporting Member

WF Supporting Member
 
TJ4Jim's Avatar
 
Join Date: Feb 2012
Location: Long Branch NJ
Posts: 2,415
Quote:
Originally Posted by Mattel View Post
a flair tool is cheap! Just pick one up for $10 at hardware store. Great idea to cut and practice on old hard line.

I found instead of steel line I found harder stainless steel lines for $10 for short one and $17 for long one.

Im re-using the main line and cube splitter and just bending the new lines, if you bend your own lines you can locate them in a place that cannot be smashed or damaged during your wheeling.

Great news on the proportion valve! You just saved me research time! u guys rock!

Well, its back to the garage tonight to paint my new trusses and more research!
Have you tried the double flare on the SS tube yet, I had a bitch of a time due to the hardness.

__________________
1999 Wrangler Chili Pepper Red

If you come to a fork in the road take it.
TJ4Jim is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Third Brake Light Problems BLACKTOOTHGRIN TJ Tech Forum 11 07-01-2010 02:44 PM
Water in my left brake light (rear) Gabe014 JK Tech Forum 5 07-23-2009 08:41 PM
Spongy pedal after disc brake conversion jsklenar YJ Tech Forum 6 07-11-2009 06:47 PM
Rear Disc Brakes? nicolas-eric TJ Tech Forum 6 12-19-2007 03:27 PM
Brake lights yelir49 TJ General Discussion Forum 7 12-03-2007 09:11 AM



Download our Mobile App

» Featured Product

All times are GMT -5. The time now is 06:09 AM.


User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC