How to do a "Factory" Rear Disk Axle Swap
#1
Member
Thread Starter
Join Date: Jan 2018
Location: Memphis, TN, Earth, Milky Way
Posts: 11,256
Received 1,731 Likes
on
1,487 Posts
How to do a "Factory" Rear Disk Axle Swap
I just did the first test-drive after finishing the swap, and I'm going to continue tweaking it, but it turned out pretty well. Same lug pattern, same leaf springs, same gears, same driveshaft, same shocks, same sway bar, same ABS connector - even the same e-brake pedal (which I though was going to be a bigger hurdle). I had to swap the wheels to 16" (and I'm just using the donor's cheap steel wheels for now), but I can still go into any parts store or Ford dealership & buy any brake or axle parts I need. That was the main reason for doing a "factory" swap instead of an aftermarket kit. There was some grinding & welding on the disk axle to put on the spring & shock mounts that fit our trucks. But even if you can't DIY, you can do the grinding and buy the parts so it's quick/easy/cheap for someone else to weld them on for you. After that, it's nearly a bolt-in swap. Even the brake line fits. Only the e-brake requires a little more fabrication.
For all the details, read the captions in this photo album:
For all the details, read the captions in this photo album:
#2
Senior Member
That's a great write-up. I have heard of this swap but never seen anyone successfully attempt it. I guess the first question I would have is - is it all worth it? Do you think the performance gained from the addition of the disc brakes made it worth the time/money spent?
#3
Member
Thread Starter
Join Date: Jan 2018
Location: Memphis, TN, Earth, Milky Way
Posts: 11,256
Received 1,731 Likes
on
1,487 Posts
Absolutely not. If you have a good rear axle in your truck, and you maintain the drum brakes properly, there's NO rationalization or justification for this swap. These brakes do NOT perform noticeably better than the old drums could.
...but that's not why I did it. My axle had been through hell (even before I started flogging it), and it had been noisy for a while. So I was heading for a(nother) replacement no matter what. And the drums were also getting thin, lumpy, and dirty, so they were due. And the shoes were coming apart (as the pics show), so they needed to be replaced soon. So rather than spend all that money & effort fixing what I had, I chose to try something I've been wanting to do for decades. The disks shed water & dirt better than drums, so they're slightly better for off-roading. But the e-brakes are still drums (inside the rotor hats), so they're still not off-road-PROOF.
But I'm glad I did it, and I'll probably do it again (when I find another good axle that cheap), at least on the '93 EB Bronco I'm building (because it has the right gear ratio), if not my '95 F150 (which would probably require regearing).
...but that's not why I did it. My axle had been through hell (even before I started flogging it), and it had been noisy for a while. So I was heading for a(nother) replacement no matter what. And the drums were also getting thin, lumpy, and dirty, so they were due. And the shoes were coming apart (as the pics show), so they needed to be replaced soon. So rather than spend all that money & effort fixing what I had, I chose to try something I've been wanting to do for decades. The disks shed water & dirt better than drums, so they're slightly better for off-roading. But the e-brakes are still drums (inside the rotor hats), so they're still not off-road-PROOF.
But I'm glad I did it, and I'll probably do it again (when I find another good axle that cheap), at least on the '93 EB Bronco I'm building (because it has the right gear ratio), if not my '95 F150 (which would probably require regearing).
The following users liked this post:
BLDTruth (06-06-2019)
#4
Senior Member
What I expected you to say - I've never understood the reason for it, purely based on a cost/benefit analysis. I've seen plenty of guys do superduty axle conversions on their pre-97 F250/F350 trucks to get the rear disc brakes, but they also get much bigger rotors/pads/calipers up front along with coil springs with radius arms, and better wheel choices with the newer lug pattern. So I can see the motivation there. But they still don't ride all that great and the brakes don't really matter unless you are hauling.
Still, cool project, and definitely one worth pursuing given you needed a new axle. Thanks for taking the time to write it all up!
Still, cool project, and definitely one worth pursuing given you needed a new axle. Thanks for taking the time to write it all up!
#5
Senior Member
Did you have to switch out the master cylinder with van's as well, or were there any modifications to get the residual pressure from drums sorted? Any issues with the ABS?