Upgrading 2002 rear end to disc brakes

cmohr · **Posted:** Tue Feb 02, 2010 8:55 pm

Lads, I was wondering if anybody has upgraded their 2002-03 model from the drum brake rear end to disc brakes. I'm in a unique position where I have an 02 CRD manual and an 04 V6 Auto. I'm changing every thing I can from the V6 to the CRD, Ie lift, bullbar, wheels and tyres, and am hoping I can switch the entire rear axles over so as (a) I get my 4.10 gears and DTT, (B) get rear discs. I ofcourse will put the drum brake rear end in the V6 to sell it off.

Any thoughts????

tjkj2002 · **Posted:** Tue Feb 02, 2010 9:11 pm

If your swapping the entire rear end then all you need is the disc brake parking cables and the 4 wheel disc proportioning valve(or 4 wheel disc ABS pump if you have ABS on the '02).

The parking brake cables are real fun to change since most of the interior needs to be removed.

cmohr · **Posted:** Tue Feb 02, 2010 9:44 pm

The 02 doesnt have ABS, The 04 does, Both have cables running to rear for handbrake, I thought that the 04 handrake drum would activate in the same manner as the 02.

I wonder if I can just get the valving done on the 02, and leave the ABS to sort out the 04???? As I would not be able to remove the ABS from the 04 because if it came out standard with ABS, it would be illegal for me to remove it.

It would really be a bonus for me to be able to switch as that would save me all the costs of pulling out front and rear rear diffs in 2 vehicles, I can just switch the front diffs over, switching the rear would be good.

tjkj2002 · **Posted:** Tue Feb 02, 2010 10:25 pm

cmohr wrote:

The 02 doesnt have ABS, The 04 does, Both have cables running to rear for handbrake, I thought that the 04 handrake drum would activate in the same manner as the 02.

I wonder if I can just get the valving done on the 02, and leave the ABS to sort out the 04???? As I would not be able to remove the ABS from the 04 because if it came out standard with ABS, it would be illegal for me to remove it.

It would really be a bonus for me to be able to switch as that would save me all the costs of pulling out front and rear rear diffs in 2 vehicles, I can just switch the front diffs over, switching the rear would be good.

Drums brakes and disc brake parking brakes use different cables,you must switch to the correct cables to have operational parking brakes.

Since the '02 does not have ABS there is no need to worry about it since the ABS before '06 used only the rear speedo sensor for the rear part of the ABS.You will need a 4 wheel disc brake proportioning valve from a non-ABS '04-'05 KJ(about $65).Putting the drums on the '04 with ABS and ment for rear discs can lead to brake issues since the drums require much less fluid then disc brakes so you could blow out the rear wheel cylinders resulting in no brakes at all for the next owner of the '04.

cmohr · **Posted:** Tue Feb 02, 2010 11:13 pm

tjkj2002 wrote:

Drums brakes and disc brake parking brakes use different cables,you must switch to the correct cables to have operational parking brakes.

Welll thats possible as I could switch out all that as well, so ... technically "DOABLE"

Since the '02 does not have ABS there is no need to worry about it since the ABS before '06 used only the rear speedo sensor for the rear part of the ABS.You will need a 4 wheel disc brake proportioning valve from a non-ABS '04-'05 KJ(about $65).Putting the drums on the '04 with ABS and ment for rear discs can lead to brake issues since the drums require much less fluid then disc brakes so you could blow out the rear wheel cylinders resulting in no brakes at all for the next owner of the '04.

Thats the worry, the Drums in the 04.... I wonder if a brake expert can add some proportioning valves so as that will work correctly, The old KJ MUST be roadworthy, as I'm not dodgy, and certainly would not want to have to live with any misfortune that the new owner may have, It will de done completely as if I was going to keep and drive it, otherwise, I'll just have to bite the bullet and pay about 1000 here to get it all changed

tonycrd · **Posted:** Wed Feb 03, 2010 2:37 pm

CMOHR, there are 02's that had ABS on the front wheels and drum brakes in the rear. There's your proportioning valve.

BUT: The '02 ABS pump is only connected to the front brakes...unlike the '04 system that also has an ABS controlled line going to the rear brakes.....Unless you can somehow plug that one and get a line directly from the master brake cilinder into the proportioning valve....or fit an ABS unit from an '02...I see no way how you can make the '04 work with drumbrakes.

I would swap the complete '04 ABS system on the '02 and fit the '02 system on the '04. You can do most of the mechanical component swapping yourself, maybe you need to swap out or reprogram the BCM...dunno. TJKJ may know.

Safest way to go..Just my 2 cents...

PS: you are swapping a Gasser lift onto a CRD???

cmohr · **Posted:** Wed Feb 03, 2010 4:59 pm

Yeah Tony, spoke with the Jeep techs, ECU/PCM?ABS, just wont be able to handle it, so I'll have to do the whole rear diff rebuild thing (twice) to switch it all over... Oh well, it was worth seeing if it was possibble..

As for the lift, I have always had a CRD lift, in my Petrol, but it is getting on a bit, I may just get some new front coils to be sure. I dont want to have to do it twice.

The 2.5 CRD Manual is a rocket!!!!

Upgrading 2002 rear end to disc brakes

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