Early Bronco Wilwood Front Big Brake Kit

Wilwood Early Bronco Front Big Brake Kit Buyer’s Guide

Upgrading to a Wilwood Early Bronco Front Big Brake Kit is one of the most noticeable improvements you can make to a 1966-77 Ford Bronco. Larger tires, added weight, and increased horsepower all demand more stopping power than the factory system was designed to provide.

Choosing the right kit comes down to three things: your model year, your wheel size, and how aggressive your build is.

Step 1: Confirm Your Bronco Year

Wilwood front brake kits are split between:

• 66-75 Bronco

• 76-77 Bronco

Because the 76-77 models came factory-equipped with disc brakes, they require different part numbers than 66-75 Broncos. Always confirm your year before selecting a kit.

Note: If you have a 66-75 Bronco but the front end has been upgraded to the 76-77 Bronco Dana 44, be sure to select the kit for 76-77 Bronco.

Step 2: Start with Your Wheel Size

Your wheel diameter determines which Wilwood kits will physically fit. This is the most important deciding factor.

Running 15" Wheels (Minimum 15" Required)

Part #140-13303 – Fits 66-75 Bronco

• 6-piston calipers

• 11.75" rotors

• Calipers available in Red or Black

• Standard Rotors (Not available Slotted / Drilled)

This is the only Wilwood front kit designed to work with 15" wheels. It’s the solution for builds keeping a traditional wheel setup while still gaining 6-piston braking performance.

Running 16" Wheels (Minimum 16" Required)

Part #140-13928 – Fits 76-77 Bronco

• 4-piston calipers

• 12.19" rotors

• Calipers available in Red or Black

• Standard Rotors (Not available Slotted / Drilled)

This kit is specifically for 76-77 Broncos and allows owners running 16" wheels to step up in rotor size and braking leverage.

Running 17" Wheels (Minimum 17" Required)

Part #140-13304 – Fits 66-75 Bronco
Part #140-13305 – Fits 76-77 Bronco

• 6-piston calipers

• 12.88" rotors

• Calipers available in Red or Black

• Standard or Slotted / Drilled Rotors Available

This is a popular performance choice for Broncos running 35" tires or heavier builds. The larger rotor increases braking torque while maintaining compatibility with 17" wheels.

Running 18" Wheels (Minimum 18" Required)

Part #140-13329 – Fits 66-75 Bronco
Part #140-13330 – Fits 76-77 Bronco

• 6-piston calipers

• 14" rotors

• Calipers available in Red or Black

• Standard or Slotted / Drilled Rotors Available

This is the largest and most aggressive front brake package available. Designed for high-horsepower builds, 37"+ tires, and heavily built rigs, the 14" system delivers maximum braking leverage and heat capacity.

Step 3: Match the Kit to Your Build

Once wheel size and year are confirmed, consider how your Bronco is used.

• Stock tire street cruiser → 11.75" or 12.19" kits are fine

• 35" tires and added weight → 12.88" kits add performance

• 37"+ tires or high horsepower builds → 14" kits offer ultimate braking power

Larger rotors increase braking leverage. More piston surface area provides stronger, more even clamping force. Together, they dramatically improve stopping control.

A Wilwood front disc brake upgrade brings modern braking authority to your 1966-77 Ford Bronco. Start with wheel size, confirm your year, and then choose the level of performance that matches your build.

If you’re unsure which Wilwood kit fits your Early Bronco, the Wild Horses team can help you select the correct setup so your Bronco stops as confidently as it runs.