Rear Disc Installation

SPP=Scott said:

The first cutting operation was done with a cutoff disc on a 4 1/2" angle grinder. I used this to removed the bulk of the flange so that I would not need to do too much grinding. Sorry for the poor picture quality.

Next step was removing the bulk of the flange with a grinding wheel. This was also done with a 4 1/2" angle grinder. This was slow work. I was really being careful not to cut into the axle tube. I got it down to about 1/16 " all the way around before proceeding to the next operation.

I then installed a 40 grit flap disc on my angle grinder to get the flange down to the same thickness as the axle tube itself. The flap disc is far more forgiving than a rigid grinding disc.

I finished the axle tube smoothing with a DA sander starting with 40 grit paper followed by 80 grit and finishing with 120 grit. This allowed me to get the axle back to a somewhat round state.

With all the grinding finished it was now time to set the flanges. I first installed new studs from an 03 durango that I purchased from the dealer. They were about a dollar each. We then tacked them in place at 2" to get an idea of what would be need to get my caliper bracket centered on the rotor. After a few tries we ended up at 1 13/16 for my 03 Durango pieces. This is time consuming in that you need to remove the axle each time you reposition the flange. Flange placement is absolutely critical. If your flange is not perfectly square on your axle tube the brake pads will not make even contact with the rotor. This was the most difficult and time consuming part of this install.

The axle flanges on the Durangos are flipped with one side having the wide pattern at the top and the other having the wide pattern at the bottom.

Once I was convinced that the flanges were square to the axle housing we finish welded them.

We did what we could to minimize warpage by using wet rags to cool between welding passes. The flanges still warped slightly. I needed to tap the studs back into alignment for the backing plates to slide on the axle smoothly.

After getting everything bolted up we checked disc run out when compared to the caliper bracket. Fortunately everything stayed square. Shown below is the completed installation.

This project took me about 12 hours to complete with some help from my friends at H Town Performance in Henderson Nevada. This does not include CNC time or parts running.


I smoothed my calipers and caliper brackets before coating them with VHT caliper paint. The logo outlines were cut from vinyl then spray painted with VHT silver caliper paint. The rotors are Ebay cheapies. I will be curious too see how they hold up, if they warp after the first time I apply my brakes I will be sure to let everyone know!

Now that I am finished I guess the question is was it worth it? To me it was. My rear end was already rebuilt with 392 gears, LSD, and all new bearings. It would have been too expensive to switch everything over to a 03-04 rear axle. With that being said, If I had it to do over again I would have gotten the axle out of the Durango I got the brakes from and built that.

I hope this post comes in handy for those that are contemplating this swap.

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SPP=Scott said:

After completing my rear disc installation I decided to post up all of the information I gathered. This post should answer most of the questions asked in regards to converting a drum brake equipped 1997-2004 Dakota/Durango to rear disc. The information has been gathered from my own experience as well as other posters. I used some images from one of 70CUDA383 posts and information from one of Duner posts for Jeep rear disc. Thanks for the info guys!
If anybody has anything to add, post it up and I will edit this thread.

This thread deals with factory rear disc options only and does not deal with any of the aftermarket offerings.

In short, there are no bolt on options for factory rear disc on our drum brake equipped Dakota/Durango's regardless of year of manufacture. All of the options require some kind of modification. Listed below are the options, positives and negatives to each, as well as what is required to make them work.

The absolute best way to swap over to rear disc is to get the complete axle assembly out of an 03-04 Dakota/Durango. If you are swapping from Durango to Dakota or Dakota to Durango the only thing that needs to be changed is the shock mounts. This is a piece of cake when compared to changing the axle flanges.


The primary reason disc brakes will not bolt onto drum brake rear ends without mods is due to the backing plate flange location. The pictures taken by 70CUDA383 show the differences in flange placement.

From these pictures it becomes obvious why the disc brake backing plates will not simply mount onto a drum brake rear end. That leaves us with needing to modify something to make this swap possible.

1. Mid 90's Jeep Grand Cherokee rear disc. This is probably the easiest swap as the Jeep uses the same axle flange location as the drum brake rear ends in our Dakota/Durango's. Duner has completed this swap and had this to say regarding modifications.

Rotors need to be redrilled for the 6-lug bolt pattern.
The center of the backing plate needs to be opened 05" to clear the larger axle tube.
The mounting holes for the backing plate need to be opened up .0625 to mount on the axle flange.
Parking brake cables have not yet been installed but, I can't see that being very difficult.
Rotors on the Jeep are a little bit smaller than what came on the 03-04 Dakota/Durango, they measure 11.2"
These rotors are solid.
This brake setup will fit under 15" wheels.

2. 03-04 Dakota rear disc. The only modification that needs to be done to use these brakes are axle flange relocation. This is not a particularly easy modification. It can be done but it is not fun.

Axle flange needs to be relocated.
Parking brake cables need to be from a vehicle with the same chassis length, they can be found at Rock Auto or obviously the dealer.
The rotors are 12.1" in diameter and are solid.
This setup uses updated single piston rear calipers.
The backing plate has an integrated caliper mount. It is a single piece unit.
This setup requires 16" or larger wheels.

3. 03 Durango rear disc. Like the 03-04 Dakota rear disc the axle flange needs to be relocated. The 03 Durango rear discs share nothing in common with the 03-04 Dakota rear discs.

Axle flange needs to be relocated and flipped on one side.
Parking brake cables need to be from a vehicle with the same chassis length, they can be found at Rock Auto or obviously the dealer.
The rotors are 12.1" in diameter and are ventilated.
This setup uses what appears to be the same caliper that was used on the mid 90's Jeep Grand Cherokee. It is a single piston caliper.
Backing plate and caliper mount are separate pieces.
This setup requires 16" or larger wheels.

The photos below show the differences between the 03-04 Dakota rear rotor and the 03 Durango rear rotor courtesy of Rock Auto. 03-04 Dakota on top with the 03 Durango below.

There may be other options. If you know of any that will work, post them up.

Well after having all this new knowledge if you still want to proceed with swapping your rear drums for discs follow below and I will show how I did it with 03 Durango rear discs.

Before starting you are going to need a pair of these. I cut these on our CNC machine when it became obvious I would need them. They were made from 3/8 plate steel. Trying to remove the factory flanges for reuse is not something I wanted to attempt.

First thing I did was remove the studs. They can be knocked out with a hammer fairly easily. Don't worry about damaging them, they are too short for the disc brakes and will need to be replaced with the proper length stud.
Don't forget to stuff some rags in your axle to protect the bearings.
Below is the stock flange before any work has been started.

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