Upgrading from Drums to Discs [Archive] - xjtalk

bluedragon436

10-25-2010, 12:06 PM

I know there are a few threads on here with people asking about how to do such a conversion, so thought I would make a thread that people can post links to other DIY writeups that might help others make the decision or gather parts to do such a conversion themselves and save some money in the process of upgrading and being able to stop better. I know that I will be gathering up the parts, and hopefully completing this upgrade as soon as I can once I get home, and will try and make a writeup of my conversion to put up on here as well.

http://cherokeekid5.tripod.com/zj_discs_on_a_xj.htm
http://naxja.org/forum/showthread.php?t=1008115
http://www.cherokeeforum.com/f51/rear-zj-disc-brakes-cherokee-xj-chrysler-8-25-a-57807/
http://home.swbell.net/rriojas3/reardisk.html
http://www.jeep-xj.info/HowtoRearDiscs1.htm\
http://www.stu-offroad.com/suspension/d35disc/d35-1.htm
http://www.jeepforum.com/forum/f11/fitting-kj-liberty-rear-disc-brakes-xj-cherokee-8-25-axle-750112/

Other Ideas if you don't mind spending the money on new parts, or just prefer brand new name brand setups

http://www.jeep4x4center.com/jeep-brake-parts/ssbc/cherokee_xj.htm
http://www.jeep4x4center.com/product-information.asp?number=D35DISC
http://www.quadratec.com/products/product_search.php?cn=Brake+Conversion+Kits&c=161

TeXJ

11-04-2010, 06:08 PM

thanks for the info!

bluedragon436

11-04-2010, 07:34 PM

Hey I just hope it will be of help... I know the links have been very helpful to me... will def. be hitting up the PNP that we have near by and grabbing as many parts as I can there, and whatever I can't I will look into purchasing new at the local parts stores....

modestmar00xj

11-30-2010, 01:10 AM

cool thanks man!

ice_cold

11-30-2010, 08:49 AM

Guess I should have taken pics. While waiting for a radiator, put discs on the rear, I have the 8.25. Now looking at the WJ(?) front upgrade.

steph74

11-30-2010, 10:31 AM

thread put in favorites, we never know. Thanks for taking the time to collect all the info;)

XJ Rat

11-30-2010, 01:25 PM

My disc set up came off a TJ. They are a direct bolt on...except for the parking brake. Stock XJ cables are too short.

bluedragon436

11-30-2010, 10:38 PM

Yeah I have also heard using the KJ brakes are a complete bolt on.. as it has a CH 8.25 axle on it, you just have to grab the KJ brake cables for the parking brakes.. or make your own setup... but chances of finding a KJ sitting in the JY that you can grab the brakes off of are slim to none... at least up here... Yeah I wanted to do the WJ front brake upgrade eventually... but that is a whole other thing...

PolarXJ

12-17-2010, 02:52 PM

Thanks for the info, my FIL is looking to convert his rig here soon. I got lucky with my conversion. I won a lift kit from Tera Flex for a TJ and was able to trade for their conversion kit.

Gabriel J

01-17-2011, 03:14 PM

need to use a proportioning valve from a dakota if Iam correct.. Your brake set up isnt set up for the force that Disc's need in the rear.. Iam runnig disc on mine just to save my axles from walking when i snap them.... :cool:

bluedragon436

01-17-2011, 04:15 PM

You can either run the valve out of a Dakota/Durango, or a ZJ w/ rear disc brakes... so pretty much if you are running a ZJ YJ setup... you can grab the valve while you are there and have the complete setup ready to go...

teamwestoutdoors

01-17-2011, 05:05 PM

Will the ZJ discs mount on the Dana 35 as well as the 8.25?

bluedragon436

01-17-2011, 05:13 PM

yes they will... they will bolt onto a D35 cause that is what they are from... with just a small bit of filing or running a dremel they will just about bolt onto the 8.25..

teamwestoutdoors

01-17-2011, 05:21 PM

yes they will... they will bolt onto a D35 cause that is what they are from... with just a small bit of filing or running a dremel they will just about bolt onto the 8.25..

Good. I've seen a lot of theadstalking about the 8.25 but not much on the 35's. I have a buddy that's going to be parting out one this year and have been thinking of this upgrade.

TeXJ

01-17-2011, 05:23 PM

why waste time and money on a Turdy5?

Mudderoy

01-17-2011, 05:24 PM

Good. I've seen a lot of theadstalking about the 8.25 but not much on the 35's. I have a buddy that's going to be parting out one this year and have been thinking of this upgrade.

It's been generally accepted that a Dana 35 is an explosion waiting to happen. That a C8.25 (at least the later ones) have about the same strength of a Dana 44.

TeXJ

01-17-2011, 05:39 PM

hey muddy speaking of 8.25s with 4.56 gears, how do you like your gearing? too low or just right?

Mudderoy

01-17-2011, 05:48 PM

hey muddy speaking of 8.25s with 4.56 gears, how do you like your gearing? too low or just right?

I love it, unless it's the cause of my heat creep. After hearing from donth8(sp?) that has the same set up just 35" tires and the same heat creep issue I don't think it's the gearing. Specfically the RPM that the engine turns at highway speeds.

I barely have to tap the accelerator to go up and over large mounts. It's great.

TeXJ

01-17-2011, 06:16 PM

That is next on my least of "things I'd like to do to my jeep but dont have enough funds" About how much was the total cost? If i may.

teamwestoutdoors

01-17-2011, 06:28 PM

It's been generally accepted that a Dana 35 is an explosion waiting to happen. That a C8.25 (at least the later ones) have about the same strength of a Dana 44.

A guy my wife works with had an XJ with an 8.25. I'm negotiating with him for his axles. His jeep is a four cylinder so it has the 4:10's in it as well.

bluedragon436

01-17-2011, 06:50 PM

Yeah you def. can't argue with that... especially if you can get it on a good deal them.. what year is the XJ he has?? Just want to look for the HP D30, and if you can get one that is a non vac. disconnect... but either way the 8.25 is an awesome upgrade if you can get it on a deal like that

teamwestoutdoors

01-17-2011, 08:56 PM

I have a 90 Limited. I have already swapped in a non disconect HP D30 for the front. But, I'm not sure if his is a non disc. I mostly just want the 4:10's and spare shafts out of his. But it will be awhile before he will sell and my brakes blow. So I want to put the zj discs on my 35 then put them on the 8.25 later on.

TeXJ

01-17-2011, 10:10 PM

what year model is his xj? then you could look that up if the disconnects came in that year. It was around 89 90 that they stopped putting in the non disconnect, I know the 91 dont have them.

teamwestoutdoors

01-18-2011, 10:08 AM

His is a 92. So, are you saying that the non discos can in the XJ's after about 91?

TeXJ

01-18-2011, 02:13 PM

yes for sure 91 and later are the non disconnect version in XJ's, in YJ's they used the disconnect version till the TJ came out. But before you do that you could always just take a peek under and see if it has a disconnect unit or not, who know if that is the original axle. ya know.

teamwestoutdoors

01-18-2011, 08:26 PM

Oh they are original. He's. Not done any nods to it at all. I just wasnt sure about what year they stoped installing the disconnected 30. I really appreciate the help.

LizardRunner

01-18-2011, 08:33 PM

91 was the last year for the disco rears in XJ's. 96 up have the low pinion D30 up front.

LizardRunner

01-18-2011, 08:36 PM

strength of the D44 vrs the C8.25 is almost negligble, key word, almost. both can be upgraded axle strength wise and many parts are available for both. IMHO an XJ with either on both ends would be awesome.

teamwestoutdoors

01-18-2011, 09:12 PM

91 was the last year for the disco rears in XJ's. 96 up have the low pinion D30 up front.

Disconected rears? Like the Dana 35?

TeXJ

01-19-2011, 05:51 PM

Disconected rears? Like the Dana 35?

Yeah i'm not following what you are saying either, the one you quoted, Outdoors

teamwestoutdoors

01-19-2011, 10:01 PM

Im unaware of a disconnected 35. That's where I got lost. I assume he ment the disco 30. But I tend to learn something new everyday.

TeXJ

01-19-2011, 10:17 PM

no disco 35, some have c-clips, but no Disconnects.

88AMCOMANCHE

01-19-2011, 10:30 PM

would love to have disc on the rears instead of drums. maybe 1 day

Mudderoy

01-20-2011, 01:22 AM

would love to have disc on the rears instead of drums. maybe 1 day

Me too!

BigBear

08-13-2011, 03:28 AM

XJ Rat

08-13-2011, 09:29 AM

I am thinking of doing this conversion for the rear but my Jeep has a Stock Dana 44 would these still work?

Find an LJ or a Rubicon, the discs on the back are a direct bolt in. You will need longer e-brake cables such as those from a YJ. My XJ has a set of LJ discs on it. The PO of my XJ also had an LJ, he bent the factory 44, and replaced it with a Dynatrac Pro Rock 60. He had the old 44 axle and started comparing the brakes. Long story short, he unbolted the drums and boltd the discs on. He told me that other than the e-brake cables it was a direct bolt on.

Jeep used high pinion axles in the front until sometime in 2000 when the supply from Dana dried up. Then Jeep started using the same front axle as found in the TJ. Any XJ from 99 down that has a factory front Dana 30 will have a high pinion as these were standard. 2000 may or may not have the high pinion depending on the build date. 2001 XJ will have a low pinion. That explains why the 99 is the most desireable year to have. Updated body and interior, updated intake manifold, last full year of the high pinion axle, no '0331' cracking head issue. My 1998 definately has the factory Dana 30 axle and it is definately high pinion. I got the Jeep from the original owner.

xj98

08-15-2011, 08:36 PM

Im going to pick up zj rear brakes from the JY this weekend! I cant wait I have stock tires and it still takes forever to stop.

bluedragon436

08-15-2011, 11:17 PM

Im going to pick up zj rear brakes from the JY this weekend! I cant wait I have stock tires and it still takes forever to stop.

Want to pick me up some too?? I can't wait to get back stateside and hit up the JY, and hopefully they still have some ZJ's w/ discs, so I can get all my parts and get them all cleaned up and ready for install when I can take my leave.. I don't have too much issue stopping my 33's, and that will be even better once I get home and replace my front discs and pads.. but can't wait to have the better braking power of the rear discs.. not to mention no scratching sounds after playing in the mud.. of all the dirt stuck in my drums..

BigBear

08-16-2011, 03:13 AM

Find an LJ or a Rubicon, the discs on the back are a direct bolt in. You will need longer e-brake cables such as those from a YJ. My XJ has a set of LJ discs on it. The PO of my XJ also had an LJ, he bent the factory 44, and replaced it with a Dynatrac Pro Rock 60. He had the old 44 axle and started comparing the brakes. Long story short, he unbolted the drums and boltd the discs on. He told me that other than the e-brake cables it was a direct bolt on.

Jeep used high pinion axles in the front until sometime in 2000 when the supply from Dana dried up. Then Jeep started using the same front axle as found in the TJ. Any XJ from 99 down that has a factory front Dana 30 will have a high pinion as these were standard. 2000 may or may not have the high pinion depending on the build date. 2001 XJ will have a low pinion. That explains why the 99 is the most desireable year to have. Updated body and interior, updated intake manifold, last full year of the high pinion axle, no '0331' cracking head issue. My 1998 definately has the factory Dana 30 axle and it is definately high pinion. I got the Jeep from the original owner.

What year should I look for?

XJ Rat

08-16-2011, 12:30 PM

What year should I look for?

Pretty sure it is a 2004. Look at http://www.onboardair.com/index.htm that is the LJ my brakes are from.

xj98

08-16-2011, 03:24 PM

Want to pick me up some too?? I can't wait to get back stateside and hit up the JY, and hopefully they still have some ZJ's w/ discs, so I can get all my parts and get them all cleaned up and ready for install when I can take my leave.. I don't have too much issue stopping my 33's, and that will be even better once I get home and replace my front discs and pads.. but can't wait to have the better braking power of the rear discs.. not to mention no scratching sounds after playing in the mud.. of all the dirt stuck in my drums..

Well I'm acturally going to pick up 1 or 2 sets to sell if I can find some extra. I could use the extra cash. If your interested let me know.

BigBear

08-16-2011, 08:59 PM

Pretty sure it is a 2004. Look at http://www.onboardair.com/index.htm that is the LJ my brakes are from.

Just 2004 or other years too? Thats not gonna be in no Junk Yard in L.A.

xjrev10

08-17-2011, 01:31 AM

91 was the last year for the disco rears in XJ's. 96 up have the low pinion D30 up front.

This is not correct. Late 99 was when the first LP 30s start showing up. 00-01 definitely had them. Also 93+ where the non disco 30s unless the jeep had a factory 242 case. All jeeps with the 242 stock are non discos, just to clear things up.

Dodge used the CAD system till early 02!!

TeXJ

08-17-2011, 08:49 AM

This is not correct. Late 99 was when the first LP 30s start showing up. 00-01 definitely had them. Also 91+ where the non disco 30s unless the jeep had a factory 242 case. All jeeps with the 242 stock are non discos, just to clear things up.

Dodge used the CAD system till early 02!!

fixed it for ya...

bluedragon436

08-17-2011, 10:49 AM

TeXJ

08-17-2011, 11:13 AM

now are yall putting these on 8.25s or the D35s?

Or does it matter?

I'd like to do this to my 8.25

XjJeepacorn

03-26-2013, 12:38 AM

Hey I just finished this, and a tiny thing I over looked forced me to get up flipping early to get my ass over to Canadian tire and buy break lines! I haven't ran new lines yet I'm doing that when I put in the yj line etc, but I did buy some nubbins to and I have a flair kit! So it worked out! I just put on the new ends and away I went. But yeah the nubbins that were all ready on there were not ceased into the drum, but the nubs are supposed to spin so you can remove them from the drum. so the problem was the old line and the nub had basically become welded together! No amount of wd 40 or heat helped at all.... Just something to think about! I am flexible with work not all of you may be :)

http://img.tapatalk.com/d/13/03/26/emy9ebyh.jpg

^^^^^^ :( lol

http://img.tapatalk.com/d/13/03/26/u2e4u6y5.jpg

^^^^^ :D

XjJeepacorn

03-26-2013, 12:50 AM

yes they will... they will bolt onto a D35 cause that is what they are from... with just a small bit of filing or running a dremel they will just about bolt onto the 8.25..

I used my zoom zoom!

1783

:)

XjJeepacorn

03-26-2013, 01:20 AM

I was looking on a few other websites at this swap.. and am just wondering if anyone has heard that you for sure have to replace the lugs with longer ones from the ZJ, or will the stock XJ drum lugs work??

If you have steel rims yes, because the metal isn't that thick and you can get enough threaded for it to be safe. If you have aluminum rims then no. I whacked studs out of the hub on my front Dana 30 that I am swapping in, I have new hubs for it :) so what I am saying is if you have aluminum rims you can use the studs from the front Dana 30 hub and they are long enough. I think that's what you were asking right?

89Laredo

03-26-2013, 12:57 PM

Wow... Necropost.

Want to upgrade to disks? Buy an 8.8. :poke:

thesupercroc

03-26-2013, 01:22 PM

Wow... Necropost.

Want to upgrade to disks? Buy an 8.8. :poke:

I hope you are kidding right?

Going to a 8.8 would be WAY more time, work and money.

XjJeepacorn

03-26-2013, 02:29 PM

I hope you are kidding right?

Going to a 8.8 would be WAY more time, work and money.

Not to mention its a frekin' ford! Lol

bluedragon436

03-26-2013, 07:00 PM

If you have steel rims yes, because the metal isn't that thick and you can get enough threaded for it to be safe. If you have aluminum rims then no. I whacked studs out of the hub on my front Dana 30 that I am swapping in, I have new hubs for it :) so what I am saying is if you have aluminum rims you can use the studs from the front Dana 30 hub and they are long enough. I think that's what you were asking right?

Yeah that was pretty much what I was asking.. I was asking/informing others who might not know or think about them needing to be replaced as well... Can't wait to gather the necessary parts to do this upgrade on my XJ...

Wow... Necropost.

Want to upgrade to disks? Buy an 8.8. :poke:I hope you are kidding right?

Going to a 8.8 would be WAY more time, work and money.

Not to mention if you already have a 8.25 (especially the 29spline).. it'd be a waste of money to pick up a 8.8, have all the factory brackets removed and the new brackets for the XJ setup welded on... Of you could just pick up all the parts in a few hours at he PNP, and have the disc brakes on the axle you already own and have hung under your XJ... Now if you are able to do all the fabrication and welding on the 8.8 yourself... then I guess the 8.8 would be an upgrade that might be worth it...

Dredwolf

03-26-2013, 10:13 PM

I missed a chance to pull the discs off a Liberty at the Pull-A-Part, but I have read somewhere that it's even easier than ZJ discs.

bluedragon436

03-26-2013, 10:15 PM

I missed a chance to pull the discs off a Liberty at the Pull-A-Part, but I have read somewhere that it's even easier than ZJ discs.

It's def easier to put them on your XJ, as the libby has an 8.25 rear axle, so all the backing plates and such are already setup for your axle... Not to mention if you can snag em from a libby, pull the parking brake cables, as they will work with your XJ as well...

TeXJ

03-26-2013, 10:18 PM

Is there a good write up with part needed to do the libby swap? I have a 8.25 as well on my xj.

msmoorenburg

03-27-2013, 07:33 AM

Is there a good write up with part needed to do the libby swap? I have a 8.25 as well on my xj.

Check my darkside build :P it used 1/2 libby & 1/2 gc parts

http://www.xjtalk.com/showpost.php?p=131809&postcount=217

XjJeepacorn

03-27-2013, 09:08 PM

Yeah that was pretty much what I was asking.. I was asking/informing others who might not know or think about them needing to be replaced as well... Can't wait to gather the necessary parts to do this upgrade on my XJ...

Not to mention if you already have a 8.25 (especially the 29spline).. it'd be a waste of money to pick up a 8.8, have all the factory brackets removed and the new brackets for the XJ setup welded on... Of you could just pick up all the parts in a few hours at he PNP, and have the disc brakes on the axle you already own and have hung under your XJ... Now if you are able to do all the fabrication and welding on the 8.8 yourself... then I guess the 8.8 would be an upgrade that might be worth it...

I just finished my write up, I tried to be as through as possible go get the whole story out there and added problems I ran into that I haven't seen posted on any other how to, check it out!

http://www.jeepacornforum.com/viewtopic.php?f=28&t=98

XjJeepacorn

03-27-2013, 09:09 PM

I missed a chance to pull the discs off a Liberty at the Pull-A-Part, but I have read somewhere that it's even easier than ZJ discs.

Marginally, it's not that hard to make a hole bigger ;)

XjJeepacorn

03-27-2013, 09:10 PM

Check my darkside build :P it used 1/2 libby & 1/2 gc parts

http://www.xjtalk.com/showpost.php?p=131809&postcount=217

No!!!! Mine!!!!

http://www.jeepacornforum.com/viewtopic.php?f=28&t=98

:P :P :P ;) ;) ;) :P :P :P

oderdene

03-28-2013, 02:31 AM

No!!!! Mine!!!!

http://www.jeepacornforum.com/viewtopic.php?f=28&t=98

:P :P :P ;) ;) ;) :P :P :P

:smiley-laughing021::smiley-laughing021::smiley-laughing021:

ArmyGuy45

08-13-2013, 12:02 AM

why waste time and money on a Turdy5?

If you dont plan on going bigger than 33's a 35 will do just fine.

ArmyGuy45

08-13-2013, 12:06 AM

I

http://www.jeep4x4center.com/jeep-brake-parts/ssbc/cherokee_xj.htm
http://www.jeep4x4center.com/product-information.asp?number=D35DISC
http://www.quadratec.com/products/product_search.php?cn=Brake+Conversion+Kits&c=161

With this convertion what 'vechicle' would you use to replace the pads?

XjJeepacorn

08-13-2013, 12:10 AM

Those look like the zj callipers to me(crown kit) maybe you can get a part number on the callipers and find out what they are for? That kit also has the e break cables and the Tera flex kit does not. My e break cables were like 80 bucks I think something to think about. The Tera flex kit looks identical to what I have which is the zj rear discs