Tuesday's Tech Tip #1 - Disc Brakes

Before we get to the Tech Tip we have the Bronco picture of the day:

photos courtesy of Powertank


Brakes are the most important piece of equipment on any vehicle, no argument there.
Until 1976 Broncos came equipped with drum brakes on the front. These work OK when new, but when they get old and rusty (exacerbated by off-road adventuring). They don't work so well.
Once I ran into a gas station to get some gas for my lawn mower...I ran into the gas station....well actually it was a garage can, but my brakes had gone tango uniform.

So what is the best and or cheapest way to get disc brakes on your Classic Bronco?

You could buy a complete front axle from a '76 or '77 Bronco...not cheap

 photo courtesy of Tom's Bronco Parts

You could buy this kit like this one from Tom's Bronco Parts which has everything you need....(it uses Chevy Parts)

You could also rob the parts from a '76-'79 F-150 or '78/'79 full size Bronco, but you would need everything from the ball joints out. This is because the F-150 used a larger bolt pattern on their spindles.

 Ford on right, Chevy on the left

 This is the route I took, my front axle needed ball joints anyway and I had free access to a good used '77 F-150 front axle. This required me to install new tie rods (which we will go over next week).
See a great write up on the Classic Bronco Forum here

There is another route, the kit from Tom's Bronco parts above uses Chevy spindles that have the same bolt pattern as the Broncos, in addition, the Ford disc brake hub from an F-150 will fit the Chevy spindle. Luckily these parts are available cheap from wrecking yards. So if you don't mind using bowtie parts on your Bronco.....

Here is the list of parts you will need:

Junkyard pieces:

• One pair of spindles from a 1972-1979 Chevy/GMC Blazer/Jimmy or 1/2 ton pick-up (make sure it has the Dana 44 front axle)
• One pair of hubs from a 1976-1979 (you may be able to go as late as 1986) Ford F-150.

New Pieces

• One pair of Calipers & pads for a 1972-1976 Chevy/GMC Blazer/Jimmy or 1/2 ton pick-up
• One pair of Ford rotors (better to buy new) to fit a '76-'79 Ford F-150/Bronco
• Bearings, races and seals for the F-150 hubs 
• Flexible brake lines and banjo bolts to fit the Chevy calipers
• New Master Cylinder for a '76/'77 Bronco with manual disc brakes (unless of course you have already updated your rig with a power booster). This is important as the drum brake master cylinders use a residual pressure valve.

Modifications:
You will need to grind a bit on the steering knuckle to clear the Chevy calipers.

There is one more small modification needed to make this work (although any claim this is unnecessary). Because the Chevy spindles are 1/4" longer that the Bronco spindles, you will not be able to install the snap ring to hold the spindle to the axle in unlikely event of a broken spindle...

no worries, the end of your stub axles are threaded, simply find a bolt that fits the thread and a fender washer of the correct size (slightly larger than the axle diameter)

credits
Bronco Fix
Fourwheeler
racycj