{musings-of-alfonsojon}

I’ve been working on my 2001 XJ’s brake lines for a while now on and off ever since I trusted a shop to get the job done and was disappointed with the work. I’ve been replacing the hard lines, soft lines, and parking brake lines, which has been difficult though doable. I purchased a pre-formed brake line kit which, while saves time, is not without its quirks.

Safety first

Wear eye and ear protection. You do not want rust in your eyes and ears.

Tie up your hair or wear a hat.

Wear gloves. Brake fluid is very bad for your skin and your XJ’s aging paint; wipe it off immediately.

Support the Jeep on both axles using jack stands or use wheel chocks and do one axle at a time. Do not rely on a jack alone.

Getting started

If your existing brake calipers, rotors, and drums are in good shape, you may reuse them. I recommend new hardware for a complete and quicker job.

• Front Rotors
• Front Calipers
• Rear Drum Cylinders
• Brake Lines
  • For ’97-01 w/o ABS:
    • Dorman 919-236 Stainless Steel Preformed Brake Line Kit
    • Brake line U-clip

Leave your old brake lines in place as a visual reference until the new ones are clipped in and connected.

Disassembly

• Loosen the lug nuts before lifting the vehicle in the air.
  • If the XJ is already on jack stands, you can try engaging 4WD-Low to add resistance, then try removing the lugs.
  • If 4WD-Low does not engage, return the vehicle to the ground and loosen the lugs.
  • Do not attempt to shift into 4WD-Low with the vehicle running off the ground as this can damage your transmission and transfer case.

Give yourself work room

Once you are ready, some preparatory work is needed. To have the most work room available, disconnect and remove the following where possible:

• Battery
• Airbox
• Vacuum lines running to intake manifold
• Vacuum line running to airbox
• A/C lines
• A/C drier

If you are also replacing your rear parking brake lines, you may also cut the parking brake cables at the rear of the parking brake equalizer and on the rear of the backing plate. Do not cut the parking brake cable running to the front of the vehicle unless you are ready to remove the center console. Once cut, remove the metal parking brake wire from the sheathing. To remove the remaining pieces of the line, a 13mm wrench will fit over the compression fitting. While not necessary, cutting the line and removing the cable core made it easier to remove on my vehicle.

Master cylinder

If the master cylinder is original, replace it now to prevent contaminating your new lines with old brake fluid, rust, and sediment.

Steps to bench bleed your Master Cylinder:

1. Install the bench bleed plugs into the ports on your master cylinder
2. Mount the master cylinder securely so that it is horizontal and will not move.
3. Using a dowel or a plastic push tool, gently depress the cylinder piston up to ~1″ of travel. Do not exceed this as you may damage internal seals.
4. Hold the piston inward for about 10 seconds and gently release the tension. Do not do this too quickly as it can cause cavitation & bubbles.
5. Once the piston feels very firm and can no longer be moved beyond ~1/8″, you may install the master cylinder into your vehicle. Leave the bench bleed plugs installed until you are ready to bleed your vehicle’s brakes.

Front lines

These runs are tight, especially on the passenger side. If your A/C is discharged, removing the lines and drier creates space; the steps below assume you can.

Driver side

• Follow the factory path around the steering shaft.
• Pass the new line through the top fender hole.
  • Replace the grommet if yours shows any signs of dry rot.
• Connect the new line to the caliper soft line; new hardware is recommended.
• Remove the old driver side line from the proportioning valve.
• Connect and hand-tighten the new line to the proportioning valve.
  • The line will only fit in the correct hole, so don’t worry about picking the wrong one.
• Cut and remove the old line, taking care to not nick your new line.

Passenger side

• Start at the left side of the firewall. The line will come in two halves.
• Route the new line through the top fender hole.
  • Replace the grommet if dry rotted.
• Clip into the OEM retaining clips as you route the line.
• From the driver side, route the line behind the factory ground and vacuum lines. Clip into OEM retaining clips as you route the line.
• Connect and hand-tighten the two line halves at the passenger side firewall. You may need to make minor bends.
• Remove the old passenger side line from the proportioning valve
• Connect and hand-tighten the new line to the proportioning valve.
  • The line will only fit in the correct hole, so don’t worry about picking the wrong one.
• Cut and remove the old line, taking care to not nick your new line.

Rear Lines

Rear soft line

The rear soft line will often be seized in place on the support bracket. First, I used snips to cut the hard line at the fitting to the soft line. I then cut the soft line flush with the U clip using an oscillating saw, then used a chisel to hammer the remaining pieces off.

At the axle, the line is secured in place by the axle breather tube. Remove the brake line by loosening the axle breather. The axle breather is supposed to spin, but it may be seized. PB Blaster may help. If not, the axle breather tube is flexible and can be spun without much care.

To install the new line, connect a new U clip and latch the new line in place.

Rear center line

The rear central hard line is tricky.

• Route the line up through the engine bay from the bottom of the vehicle. A second person is valuable for this part.
• Ensure the line is routed around the steering shaft, following the OEM routing.
• Once routed, disconnect the OEM line from the proportioning valve and connect the new line finger-tight.
• Retain the factory spacer for the rear center line and the front left line. This prevents the lines from touching.
  • If you do not have this or it breaks, you can get creative with zip ties or foam.
• Route the line above the rear parking brake equalizer.
  • If you do not, you may need to remove the equalizer assembly to clip the line in place.
  • If your equalizer is stuck to the frame, consider removing the line and trying again.

Rear axle lines

Passenger rear line

The passenger side rear axle line is caged in place. My vehicle had two bolts, despite having three bolt holes on the cage. Once the cage is removed, you can route the new line to follow the old line.

• Disconnect the old line from the wheel cylinder
  • Remove the old cylinder if replacing
• Connect the new line to the wheel cylinder
  • Do this before mounting the cylinder if replacing
• Install the brake line cage over the brake line
• Connect the new line to the rear axle soft line
  • You may need to bend the line a bit to get it to fit properly.

Driver rear line

• Disconnect the old line from the wheel cylinder
  • Remove the old cylinder if replacing
• Connect the new line to the wheel cylinder
• Connect the new line to the rear axle soft line

Passenger rear parking brake cable

• Cut the parking brake cable near the backing plate
• Cut the parking brake cable near the equalizer
• Remove the metal line
• Use a 13mm wrench or socket to release the retaining clips and remove the cable
• Route the new cable above the leaf spring
• Connect the new cable to the left side of the equalizer

Driver rear parking brake cable

• Cut the parking brake cable near the backing plate
• Cut the parking brake cable near the equalizer
• Remove the metal line
• Use a 13mm wrench or socket to release the retaining clips and remove the cable
• Remove the bolt closing the retainer on the axle differential and remove the cable
• Place the new cable in the retainer and tighten. You can replace the retainer if desired.
• Route the new cable above the leaf spring
• Connect the new cable to the right side of the equalizer

What’s Next

I still have yet to bleed the brakes, mount the rear soft line to the bracket with the U-clip, and install the rear drums along with the necessary hardware. I’ll update this post when the time comes and add some photos.