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rear disc brakes..

mikereid350

NAXJA Forum User
i have a 2000xj with 31" mtr on... i want a rear disc conversion but can't affort a store bought one... i can't get the thing to stop well,if has a new master cyl,near rear pads,rear drums,new front pads...it is only really a problem when i load it up with camping gear for and stuff plus a 16 foot alumin boat and 30 hp motor...i need more brake power.....its ever worse is the winter snow if always locks up the front and never will lock the rear even on hard packed ice coved road... oh ya its got a 8.25 diff
 
mikereid350 said:
i have a 2000xj with 31" mtr on... i want a rear disc conversion but can't affort a store bought one... i can't get the thing to stop well,if has a new master cyl,near rear pads,rear drums,new front pads...it is only really a problem when i load it up with camping gear for and stuff
So the problem is only when you're really loaded up? Well, make sure that your brakes are adjusted right, consider getting a D44 with bigger drums, or check out the yards and get the Grand Cherokee stuff and bolt it on (ok it's a near bolton).

16 foot alumin boat and 30 hp motor...i need more brake power....
You are using a brake controller when you tow, right?
 
I know there have been alot of posts on this, so I decided to bring back an old one.

Does anyone know if the Dana 30 calipers are the same as the rear ZJ calipers? I have a extra set and was wondering if I could use them.

Also, some of the write ups talk about needing a custom spacer machined to fit on the shaft outboard of the axle seal, to ensure the bearing sits in the race properly, and some of them dont mention this. Is it needed? Does it depend on year or what?

Thanks guys
 
PoSxJ said:
I know there have been alot of posts on this, so I decided to bring back an old one.

Does anyone know if the Dana 30 calipers are the same as the rear ZJ calipers? I have a extra set and was wondering if I could use them.

Also, some of the write ups talk about needing a custom spacer machined to fit on the shaft outboard of the axle seal, to ensure the bearing sits in the race properly, and some of them dont mention this. Is it needed? Does it depend on year or what?

Thanks guys

No the calipers are different. The spacer is required on retained axle shafts. If you are doing the 8.25, it's c-clipped. If you are doing a Dana 35, then you are more than likely using a rubicon retaining plate which has this spacer built in. If it's a dana 44 and you aren't doing the work to make the rubicon plate fit. Then you need a spacer made.
 
91 Jeep Project said:
No the calipers are different. The spacer is required on retained axle shafts. If you are doing the 8.25, it's c-clipped. If you are doing a Dana 35, then you are more than likely using a rubicon retaining plate which has this spacer built in. If it's a dana 44 and you aren't doing the work to make the rubicon plate fit. Then you need a spacer made.

So a spacer is needed on a Dana 35, and 44, but not the 8.25. Is this correct?

Thanks
 
91 Jeep Project said:
No the calipers are different. The spacer is required on retained axle shafts. If you are doing the 8.25, it's c-clipped. If you are doing a Dana 35, then you are more than likely using a rubicon retaining plate which has this spacer built in. If it's a dana 44 and you aren't doing the work to make the rubicon plate fit. Then you need a spacer made.
I keep seeing people repeating this myth that the Rubicon D44 retainer plate (mopar pn 5083678AA) will work with the D35 non-clip.

Having believed all the "expert" advice on here, I bought a set when I did my Crown Vic disk brake swap. Yes the fit the backing plate nicely and the bolt pattern matches. Problem is that the ID of the retainer plate lip was 2.52" and the OD of the outer seal is 2.55". 15-thousands contact is simply not enough contact area, especially if there is any slop in the retainer bolts holes mounting holes. The raised lip is also too tall. The CV backing plate is about 0.140" thicker, but the raised lip on the retainer plate is 0.225". I fabbed a set of spacers using the old retainer plates which were 0.150" thick.
 
PoSxJ said:
So a spacer is needed on a Dana 35, and 44, but not the 8.25. Is this correct?

Thanks

As stated above if you have a non c-clip Dana 35 or a Dana 44, then you will need the spacers.

I have some spacers if anyone needs them. They came with my TeraFlex kit, but because I was installing it on a 8.25 (no c-clips) I didn't need them. Send me a PM if interested.
 
lawsoncl said:
I bought a set when I did my Crown Vic disk brake swap. Yes they fit the backing plate nicely and the bolt pattern matches.

I am lost here. Crown Vic is recommended for the XJ 44 (not the 35/TJ 44/8.25) because the end patterns are the same. You're saying that you got a Rubicon 44 retaining plate to fit the XJ 44 pattern without modifying it?
 
91 Jeep Project said:
I am lost here. Crown Vic is recommended for the XJ 44 (not the 35/TJ 44/8.25) because the end patterns are the same. You're saying that you got a Rubicon 44 retaining plate to fit the XJ 44 pattern without modifying it?


The D35 non-clip and the TJ D44 don't have the same retaining bolt pattern (not sure why I said they matched- brain fart I guess). I was planning on redrilling them as mentioned in http://jeepin.com/features/cvdiscs/index.asp. Based on other writeups, the Crown Vic backing plate slides right onto the XJ D44, so I'm pretty sure theXJ D44 and Crown Vic have the same retaining bolt pattern.

Here's the dimensions I took off the TJ Plates I ordered.
[SIZE=-1]Jeep Wrangler Rubicon 2003+, [/SIZE]part number 5083678AA
Thickness 0.15"
Lip Height 0.225
Hole ID 2.52
Hole OD 2.75

Top Hole Horiz Spacing 3.55" ~ 90 mm
Bottm Hole Horiz Spacing 3.18" ~ 80 mm
Top-Bottom Spacing Vert Spacing 1.55" ~40 mm
 
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