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.
If someone would have some rings built about the thickness of the depth difference of the drum axle and the disc axle, we could adapt the Dakota/Durango discs to a Drum brake axle with out cutting or welding, and then use counter suck bolts on adapter rings to screw to existing axle ring, but there would have to be eight holes in each ring with four counter sunk and four with new bolts to attach to disc backing plate, so the discs would not be clocked the same as stock, but it would not be a big deal and if the other four were counter sunk on the flip side, they would work on a Dakota and Durango backing plate just by flipping it over.