1980 Toyota rear disc brake conversion

[Tim]

1994 Toyota 2WD Calipers, 1980 4WD rotors and custom CNC'd bracket. 

[Tim]

Ground down axle hub to fit 1980 4WD rotor.

[Tim]

Mounted rotor, but first I had to drill the rotor stud holes to 15/32".

[Tim]

Mounted rotor and caliper for spacing to later CNC a bracket.

[Tim]

CNC'd bracket and then mounted the caliper to the rotor.

[Tim]

Mounted tire to finish the assembly.

[Tim]

A normal view to see the depth of the caliper exposure.

[Tim]

1980 Toyota rear disc brake conversion parts.

Caliper:  V-6 1994 4-runner w/ a 12S to house a 12.5mm rotor.

Rotor: 1980 front rotor or one that is 11.8" diameter, 48mm wide, 12.5mm thick 6x5.5 bolt pattern.

Hardware: (4) M10 x 1.25, 50mm flange bolts
        (4) M10 x 1.25, 40mm flange bolts
        (8) M10 x 1.25 flange nuts
        (8) M10 washers
        (8) M10 lock washers
        (4) 1/2" - 20 2 inch cap bolts
        (4) 1/2" - 20 nuts
        (4) 1/2" lock washers

Brackets:  7 x 6 x .625" (LxWxH) 6061-0 aluminum stock which can later be heat treated.

[Tim]

 all for less than 150 bucks.

[Mytattootears]

dude this is cool man, i like it, wanna help me do this? good job man im going to try this once i get my truck driving correctly

[hilux-1983]

Everything looks good but, what about braking line pressures etc....? Any need for different valving?

[Tim]

When I added the lift I had already installed a manual proportioning valve.  I do not have the one inch bore master cylinder and am able to stop pretty quickly with the 3/16" lines that the master cylinder feeds.  I see no reason to upgrade due to the truck stopping with one pedal depress. 

[Tim]

dude this is cool man, i like it, wanna help me do this? good job man im going to try this once i get my truck driving correctly

Where are you from?

[toy yoda]

That's a beautiful thing!! Just one question those are stock toyota calipers? I have been looking at swiching my over, and I was woundering how much a difference it makes?

[UndefinedTaco]

15's or 16" wheels?

Simple swap..there are a ton of different ones out there now..
Subscribed for future use.

[Tim]

Yes they are stock Toyota calipers.  They are off a 2WD ( I believe ) 1994 Toyota 4 runner, they are S12W calipers if that makes a difference.  I have no issues braking running 15 x 12.5's.  < also to answer the rim sizing question. 

I went to Hollister this past weekend and I did not run into any issues.  I went into a pretty off camber ravine at the foot of the ridiculous course that you see upon entering the new obstacle park (to the right when you get to the bottom) and through the mud and water and over plenty of rocks from the trails and old obstacle course.

All in all I am pretty happy and although bigger is better it's also overkill where it is not necessary on a budget unless your into bragging I guess.  My truck stops well and I have not had an issue if it helps anyone out that is interested in doing this conversion.

[Tim]

It looks as if the Yukon axles bought from Marlin will be sold in the condition to mount a set of rotors with no extra fab work.  Unless they are the same diameter on the outside hub as stock.  Stock, the Toyota axle is slightly chamfered which makes grinding easier but it takes time.  I put my truck up on blocks and fired it up to make the grinding easier and look clean.  Be careful of the studs catching loose clothing as this could cause serious injury or death.