Why Install a Wilwood Hydraulic Handbrake?

A hydraulic handbrake transforms how you control your car on the track. Unlike a mechanical cable handbrake, a hydraulic unit uses brake fluid from your existing system to apply the rear brakes independently. This gives you two key advantages: precise lock‑up control for initiating drifts or sharp turns, and the ability to hold the car stationary without straining cables. Track enthusiasts choose Wilwood for their reputation in racing components—consistent pressure, durable construction, and easy integration into most braking systems.

Before you begin, understand that this installation is a moderate mechanical project. You need basic wrench skills, familiarity with brake bleeding, and patience to get the hydraulic connections leak‑free. This guide assumes you are converting from a mechanical handbrake or adding a secondary hydraulic handle for performance driving. Always check local regulations: in some regions, a hydraulic handbrake is track‑use only and may not be street legal.

Tools and Materials Needed

Having everything ready before you start saves time and prevents frustrating trips to the hardware store. The Wilwood hydraulic handbrake kit typically includes the handle, master cylinder, mounting bracket, and hardware. You will also need:

  • Wilwood hydraulic handbrake kit (choose the model that fits your chassis and brake line thread: 1/8" NPT or AN‑3).
  • Brake fluid – Use DOT 3, 4, or 5.1 compatible with your vehicle. Avoid DOT 5 silicone unless your entire system is designed for it.
  • Wrench set – Metric and SAE sizes, 8mm to 19mm, plus line wrenches for brake fittings (10mm or 3/8" are common).
  • Socket set with extensions and a ratchet.
  • Drill and drill bits – For making mounting holes in sheet metal or brackets. Use a center punch to prevent wandering.
  • Mounting hardware – The kit includes bolts, but you may need self‑tapping screws or rivet nuts for thin material.
  • Safety glasses – Brake fluid is caustic, and drilling produces metal shards.
  • Rags and a catch pan – Brake fluid eats paint. Keep it contained.
  • Brake line tubing (optional) – If you need to extend or relocate lines, use nickel‑copper or stainless steel line rated for high pressure.
  • T‑fitting or proportioning valve – Depending on your system, you may need to split the rear brake circuit to integrate the handbrake without losing independent rear braking. Wilwood offers a dedicated inline valve (#260‑13179) for this.

Preparation Steps

1. Safety First

Park the vehicle on a level surface and chock the wheels. Disconnect the negative battery terminal to prevent accidental electrical shorts. If you are working near the master cylinder, be aware that brake fluid spills on painted surfaces will strip the finish immediately.

2. Remove the Existing Mechanical Handbrake

Most cars have a lever between the seats that pulls a cable to the rear calipers. To remove it:

  • Locate the handbrake mounting bolts (usually two or four) under the console or at the base of the lever.
  • Disconnect the cable from the adjuster underneath the car or at the lever pivot.
  • Slide the lever out. Keep the cable pulleys and bracket if you plan to reuse them for the hydraulic handle mount.

Take a photo before disassembly – it helps when you reinstall interior trim later.

3. Choose the Mounting Location

The Wilwood handbrake should be within easy reach of your driving hand without having to lean forward. Common positions:

  • In the stock center console area (if space permits).
  • Mounted to the transmission tunnel or a custom bracket.
  • On the side of the driver’s seat (for dedicated track cars).

Test the lever range of motion. It needs to travel from fully forward to pulled back without hitting the seat, steering wheel, or your leg. Mark the holes with a transfer punch or scribe.

Installing the Wilwood Hydraulic Handbrake

4. Mount the Bracket and Handbrake

Drill pilot holes at your marked locations. If you are mounting into single‑layer sheet metal, reinforce the area with a steel backing plate on the underside. Use the supplied bolts or rivet nuts to secure the bracket. Torque the bolts to the Wilwood specification – overtightening can deform the bracket or crack the handle casting.

Attach the handbrake lever to the bracket. The clevis pin and cotter should move freely. Apply a drop of threadlocker to critical fasteners so vibration does not loosen them.

5. Plan the Brake Line Routing

The hydraulic handbrake becomes an inline device between your master cylinder and the rear calipers. There are two common routing methods:

  • Series (inline) – Brake fluid from the master cylinder goes to the handbrake inlet port, then from the outlet port to the rear brakes. When you pull the handle, it blocks the rear circuit and builds pressure independently. This is the simplest and most common setup.
  • Parallel with a proportioning valve – You run a separate line from the master cylinder to the handbrake, then merge back into the rear circuit via a T‑fitting. This allows you to adjust rear bias separately but requires more fittings and careful bleeding.

Whichever method you choose, route the new or adapted brake lines away from moving suspension parts, sharp edges, and heat sources. Use P‑clamps or adhesive cable ties to secure the lines every 12 inches.

6. Connect the Brake Lines

Identify the inlet and outlet ports on the Wilwood master cylinder. They are usually stamped “IN” and “OUT.” Use new copper washers (provided) on each fitting to prevent leaks. Tighten fittings with a line wrench – never over‑tighten; 15‑18 ft‑lbs is typical for 3/8‑24 fittings.

  • If using a T‑fitting, install it between the previous master cylinder line and the handbrake inlet.
  • Connect the outlet port of the handbrake to the rear brake line that goes to the calipers.
  • Double‑check that all connections are tight but not stripped.

7. Bleed the Brake System

Any air introduced during line changes must be removed. The Wilwood handbrake adds another high point in the system where air can trap. Follow this order for best results:

  1. Fill the master cylinder reservoir with fresh brake fluid.
  2. Start with the farthest rear caliper (driver side rear on most left‑hand drive cars).
  3. If your handbrake has its own bleed screw (some Wilwood models do), crack it open slightly while a helper slowly pulls and holds the handbrake lever. Close the screw before releasing the lever.
  4. Then bleed each rear caliper in the normal pressure‑bleeding method – open the bleed nipple, push pedal or handbrake, close nipple, release. Repeat until no bubbles appear.
  5. Check the handbrake lever travel. If it pulls all the way to the handle stop without resistance, you still have air. Tap the handbrake body with a wrench to dislodge trapped air, then re‑bleed it.

A pressure bleeder makes this job much easier because it maintains fluid level and prevents back‑flow of air.

Final Steps and Testing

8. Adjust the Handbrake Lever Travel

Most Wilwood handbrakes have an adjustable stop screw on the master cylinder pushrod. With the system fully bled and the parking brake released, adjust the stop so that the lever has about 1–2 inches of free travel before the brakes begin to engage. Too much free travel reduces hydraulic pressure; too little causes the brakes to drag.

Pull the lever firmly to one notch from full lock – the rear wheels should lock when the lever is about 3/4 of the way back. Test this on a jacked car (with safety stands!) or on a loose surface at low speed.

9. Test Functionality

  • With the engine running, depress the brake pedal and pull the handbrake. The pedal should not drop – the hydraulic circuit must be closed.
  • Release the handbrake and check that the rear wheels spin freely. Drag indicates residual pressure.
  • Drive slowly and apply the handbrake briefly. The rear should lock evenly side‑to‑side. If it pulls to one side, you have an air bubble in that caliper or an obstruction in the line.

10. Clean Up and Trim Reinstallation

Wipe up any stray brake fluid immediately with rags and isopropyl alcohol. Reinstall interior panels, making sure nothing pinches the handbrake lines. Leave a small access panel if possible for future bleeding.

Maintenance Tips for Track Use

Hydraulic handbrakes require more frequent attention than mechanical ones because the fluid absorbs moisture and can boil with repeated heavy use. Replace brake fluid every season or after every three track days. Inspect the handbrake master cylinder for leaks at the pushrod seal – a weep here can drip fluid inside the cabin.

Also check the mounting bolts regularly. The lever endures high forces, and looseness will cause inconsistent braking.

Common Pitfalls and How to Avoid Them

  • Air trapped in the handbrake – If you cannot get a firm lever, tilt the car slightly to raise the handbrake as the highest point, or use a syringe to back‑bleed through the caliper.
  • Incorrect thread pitch – Wilwood uses 1/8″ NPT for some kits, while others use -3 AN. Verify the thread before buying adapters.
  • Routing lines through the firewall – Always use a grommet to prevent chafing. If you drill a new hole, deburr it thoroughly.

Where to Find More Information

Conclusion

Installing a Wilwood hydraulic handbrake is a rewarding upgrade that gives you finer control over your car’s rear braking. The process is straightforward if you take care with mounting, line routing, and bleeding. Once set up correctly, you will appreciate the instant response and ability to lock the rear wheels on demand – a game‑changer for track driving, autocross, and performance events. Take your time, bleed thoroughly, and test in a safe area before hitting the track.