Here are some pics of my little 12b build. I did the disc brake conversion from the tech articles, replaced seals, and put in a longer center hose for the brakes. I also dropped in a mini spool at the same time. I used the backing plates and calipers from my old stock 10b front that I had laying around. (I did end up buying new calipers since one of my old ones was shot. But they are pretty cheap). This doesnt have any provisions for an ebrake.
The part numbers and prices were:
Mini spool- Richmond #836-78-1230-1836-78-1230-1 from Jegs 89.99
Rotors for an 89 K1500 P/U (2)- #5977RG Checkers 22.99ea
Brake lines for calipers (2)- #4136847 Napa 10.99 ea
Longer center brake hose- #4138068 Napa 16.99
Axle seals (2)- 16044 Checkers =2.39 ea
Conversion Ujoint for 12b to old 10b shaft(S44 to 1310)- Neapco 3-3130, Checkers part number is 215-0356 10.99
Brake calipers for an 84 K5 front- 184208/184209 12.99 (w/20.00 core)
1st I took off the old brake drum parts and axle shafts.
You have to remove the center pin and bolt, plus the spider gears to get to the side gears and c-clips.
Side gear and c-clip.
Axle shaft is gone.
Drums are gone, now onto the old seal.
I swapped in the new seals
Then I moved onto the backing plates.
I had to remove the lip/cup around the center opening since it wouldnt let the axle shaft go in enough to put the c clip back.
So I ground it off.
Next I drilled a couple of new holes and elongated a couple of the old ones (I know their not pretty, but it was trial and error at first ). You can see my orientation markings on where I wanted the caliper to sit (12 oclock/6 oclock).
Once the backing plates were done, and my calipers ready. It was time to start assembling them. After many test fittings I finally was able to get everything to go together the way I wanted them.
I bolted the backing plates on with new hardware. Then I installed the axle shafts. Next came the new rotors. I had the center section machined out by a local shop. The hub diameter on the 12b was 3.578, the local shop machined the centers out to 3.581 (their next available size). The machine work cost me 30 dollars, and was done overnight.
Then I installed the calipers and fresh pads, along with the brake lines. I was able to rebend the old steel lines on the axle so I could run the hoses out of the way.
In the pic above, you can see that I had to grind quite a bit from the lower edge of the brake pad (and a little bit off the lower projections of the calipers). I kept getting some contact between the pad and rotor hat.
I have had no issues after removing all of that material, and the brakes have been on my DD for 3-4 months now.
As I was doing the swap, I was also dropping in the mini spool. It was a pretty easy, straight forward install.
After removing the spiders and sidegears, I installed half of the spool inplace of one of the side gears.
I then re-installed the c-clip, and repeated the process for the other side.
I then installed the spools center blocks. I did have to bevel the inner edges a bit to get them to install correctly.
I then rotated it and re-installed the centerpin and bolt.
Overall, I think both of these mods came out pretty good. Braking was improved and the spool has helped out tremendously. I also really like it in the snow and ice packed roads. I've slid a few times driving to work before doing this, and with the spool installed it was 100 times more predictable and easier to recover from any sliding.
Z
The part numbers and prices were:
Mini spool- Richmond #836-78-1230-1836-78-1230-1 from Jegs 89.99
Rotors for an 89 K1500 P/U (2)- #5977RG Checkers 22.99ea
Brake lines for calipers (2)- #4136847 Napa 10.99 ea
Longer center brake hose- #4138068 Napa 16.99
Axle seals (2)- 16044 Checkers =2.39 ea
Conversion Ujoint for 12b to old 10b shaft(S44 to 1310)- Neapco 3-3130, Checkers part number is 215-0356 10.99
Brake calipers for an 84 K5 front- 184208/184209 12.99 (w/20.00 core)
1st I took off the old brake drum parts and axle shafts.
You have to remove the center pin and bolt, plus the spider gears to get to the side gears and c-clips.
Side gear and c-clip.
Axle shaft is gone.
Drums are gone, now onto the old seal.
I swapped in the new seals
Then I moved onto the backing plates.
I had to remove the lip/cup around the center opening since it wouldnt let the axle shaft go in enough to put the c clip back.
So I ground it off.
Next I drilled a couple of new holes and elongated a couple of the old ones (I know their not pretty, but it was trial and error at first
). You can see my orientation markings on where I wanted the caliper to sit (12 oclock/6 oclock).
Once the backing plates were done, and my calipers ready. It was time to start assembling them. After many test fittings I finally was able to get everything to go together the way I wanted them.
I bolted the backing plates on with new hardware. Then I installed the axle shafts. Next came the new rotors. I had the center section machined out by a local shop. The hub diameter on the 12b was 3.578, the local shop machined the centers out to 3.581 (their next available size). The machine work cost me 30 dollars, and was done overnight.
Then I installed the calipers and fresh pads, along with the brake lines. I was able to rebend the old steel lines on the axle so I could run the hoses out of the way.
In the pic above, you can see that I had to grind quite a bit from the lower edge of the brake pad (and a little bit off the lower projections of the calipers). I kept getting some contact between the pad and rotor hat.
I have had no issues after removing all of that material, and the brakes have been on my DD for 3-4 months now.
As I was doing the swap, I was also dropping in the mini spool. It was a pretty easy, straight forward install.
After removing the spiders and sidegears, I installed half of the spool inplace of one of the side gears.
I then re-installed the c-clip, and repeated the process for the other side.
I then installed the spools center blocks. I did have to bevel the inner edges a bit to get them to install correctly.
I then rotated it and re-installed the centerpin and bolt.
Overall, I think both of these mods came out pretty good. Braking was improved and the spool has helped out tremendously. I also really like it in the snow and ice packed roads. I've slid a few times driving to work before doing this, and with the spool installed it was 100 times more predictable and easier to recover from any sliding.
Z
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