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.
