Rear Disk Brake Conversion Pt 1

[Rockdawg84]

So I had to do rear axle seals (been leaking for a while now) So I thought what the heck I'll do a rear disk conversion. I was actually inspired by some 1st gen guys on Pirate.

First pull the axle shafts and do axle seals. Done :tongue:

Next use a cutoff wheel or plasma cutter, or torch to cut around the mounting flange taking care not to put too much heat into the bearings and keep a fire extinguisher handy. rear axle oil is flammable.
Rear Disk 1 by Sam Wright, on Flickr

I used the following parts. brake rotor from the rear of a 94 Montero Sport. Rear Caliper from 94-04 Mustang Gt. Custom flex line with banjo connector.
Rear Disk Brake 3 by Sam Wright, on Flickr

Rear Disk Brake 7 by Sam Wright, on Flickr

Rear Disk Brake 8 by Sam Wright, on Flickr

Rear Disk Brake 5 by Sam Wright, on Flickr

Next you have to remove 2 of the axle bolts. We used a air hammer, but it is possible to install the axle shafts and only bolt in the bottom 2 and then drive out the top 2. These will be replaced later.

Then you have to build a bracket to hold the caliper.

Here is my prototype
Rear Disk Brake 20 by Sam Wright, on Flickr

Here is the torched bracket made of 1/4" plate
Rear Disk Brake 4 by Sam Wright, on Flickr

cleaned up and drilled and painted

Rear Disk Brake 11 by Sam Wright, on Flickr

Now you have to shim the caliper bracket so the Caliper is centered on the rotor.
Rear Disk Brake 14 by Sam Wright, on Flickr

Rear Disk Brake 13 by Sam Wright, on Flickr

Rear Disk Brake 10 by Sam Wright, on Flickr


I cut and reflared the hard line to create a better angle for the flex line.
Rear Disk Brake 9 by Sam Wright, on Flickr

Bolt it all together, bleed the brakes and there you go.

Rear Disk Brake 10 by Sam Wright, on Flickr

Reinstall the tire and enjoy extra stopping power, Brakes that don't cake up in mud and snow, and you can work on the rear end with out cracking open the brake system.
Rear Disk Brake 15 by Sam Wright, on Flickr
Rear Disk Brake 18 by Sam Wright, on Flickr


Edit: So over 9 years later I got part 2 completed. Jump to page 17 to see part 2.

 

[bike]

Nice write up with pictures! Do you notice any obvious extra stopping power or difference than before? I am fairly interested in doing a swap, although I can't see it getting done for a while. I'll keep this bookmarked for sure though. Any thoughts or ideas for a E-brake?

 

[jmt2404]

Can you feel a difference in the stopping power at all? And why can't you just use another stock runner setup? Or even better a tundra brake system (231's)

 

[Rockdawg84]

Nice write up with pictures! Do you notice any obvious extra stopping power or difference than before? I am fairly interested in doing a swap, although I can't see it getting done for a while. I'll keep this bookmarked for sure though. Any thoughts or ideas for a E-brake?

Can you feel a difference in the stopping power at all? And why can't you just use another stock runner setup? Or even better a tundra brake system (231's)

There is definitely a huge increase in braking power. Now that could be because my drum's were so oil soaked that I doubt they were doing any braking what so ever.

The reason I didn't use another toyota rear disk set up was that as far as I know there are none with axle shafts that are the same length as ours. 4th gen do have them and you could conceivably press off all the brake backing plates and press them onto our axles but to me that would be more expensive. And because of balance issues in the brake system you couldn't run a 231 caliper in the rear, it needs to be smaller.

As far as a parking brake that is why i chose the mustang caliper because it has a mechanical parking brake and I simply have to figure out the cabling thus part 2.

 

[Tucson4runner]

Great job bud

 

[Rockdawg84]

Great job bud

Thanks:surfer: it was really fun to do. like a big puzzle that if you get it wrong you could die later on. LOL

 

[ChildrenOfBodom]

You should make a blueprint of that caliper mounting plate that you made... I could have a metal shop fab some up for my truck.

Or... you could sell me some

Point is... I want. Fantastic job. Is there any way to retain the e-brake? I've got a manual...

 

[Rockdawg84]

You should make a blueprint of that caliper mounting plate that you made... I could have a metal shop fab some up for my truck.

Or... you could sell me some

Point is... I want. Fantastic job. Is there any way to retain the e-brake? I've got a manual...

Thanks, stay tuned I may make some more of the plates if there is enough interest. the E-brake should not be to hard and so that will be "Rear brake conversion pt 2"

 

[99 sr5 highlander]

Great job! Very innovative.

 

[Rockdawg84]

I specifically chose the calipers because they have been around forever and I should have easy access to parts. Also the mustang weighs a little over 3000 lbs and so I thought that they would be a good balance for the front 13WL's. And they have a mechanical parking brake.

So a few thoughts now that I'm all done. Except the ebrake.

Pro's
1. super clean setup and stops wicked nice.
2. easy rear pad changes.
3. I can get into the rear axle with out breaking open the brake system. I hate bleeding the brakes just to change a 3rd member.

Cons
1. expensive and a lot of work to get it done. About $560 since I bought everything new.
2. I may need to upgrade my master cylinder because the pedal is a little softer than I normally like. Maybe a 1-1/16 bore or 1-1/8. I think this is partly because I have already moved up to the 13wls and together with the rear calipers I could use the extra volume.

 

[jmt2404]

So if I was to run across a 4th gen rear axle I could possibly pull the brake system off it and put on mine and make it work? Rotors, calipers, mounts and other associated parts and do the conversion on mine?

Nice write up and it seems pretty easy. Maybe one day I'll get around to doing this upgrade.

 

[Dous]

You should make a blueprint of that caliper mounting plate that you made... I could have a metal shop fab some up for my truck.

Or... you could sell me some

Point is... I want. Fantastic job. Is there any way to retain the e-brake? I've got a manual...

Universal - B&M Brake Line Lock - Universal product

Line Lock!

 

[fightman80]

very cool conversion Rockdawg!

 

[Gerdo]

Universal - B&M Brake Line Lock - Universal product

Line Lock!

Line Locks will bleed off pressure over time. Not good for a P-brake.

Also not much of a third leg when using the P-brake to feather the brakes off for rock crawling.

 

[Stick Figure]

So if I was to run across a 4th gen rear axle I could possibly pull the brake system off it and put on mine and make it work? Rotors, calipers, mounts and other associated parts and do the conversion on mine?

Nice write up and it seems pretty easy. Maybe one day I'll get around to doing this upgrade.

4th gen appears to have a different bolt pattern on the axle itself to give it a wide enough spread for the caliper brackets to bolt to. I haven't confirmed it first hand, but from the service manual images that is the appearance.

 

[blcktpgsr]

Sweet, I have heard of this conversion but never really seen one done. This is a trend/mod that will populate within the 3rd Gen community for sure.

Great!

 

[PitbullRescuer]

Good work. I've wanted to do a rear disk conversion for a while, great write up!

 

[russ_]

Great write up! Where did you get the flex lines made? Local shop or ordered from somewhere?

 

[Rockdawg84]

Great write up! Where did you get the flex lines made? Local shop or ordered from somewhere?

Thanks, I got the flex lines made up at a local shop called "Hose Power" cost for 2 was $51.

 

[Rockdawg84]

4th gen appears to have a different bolt pattern on the axle itself to give it a wide enough spread for the caliper brackets to bolt to. I haven't confirmed it first hand, but from the service manual images that is the appearance.

I'm out of town for a couple of days but when I get home I will crawl under my wife's 4th gen and do some measurements.