Jeep Cherokee Forum

Jeep Cherokee 1984-1996: How to Replace Brake Master Cylinder

A bad master cylinder can change the feel of your brake pedal and affect the efficiency of your brakes. Learn how to replace it here on your Jeep Cherokee.

By Jeremy Perrod - August 24, 2015

This article applies to the Jeep Cherokee XJ (1984-1996).

A bad master cylinder could change the feel of your brake pedal entirely. For starters, your brake pedal will feel spongy. This means you will have a lot of pedal room before the Jeep Cherokee starts braking, and when it does, it won't stop as fast as it usually does. Since the master cylinder is a hydraulic system, it can easily introduce air into the braking system, thus affecting the brake performance. It is critical that you don't drive the car when you feel a change in braking. Here's how to replace the master cylinder and save some money.

Materials Needed

  • A ratchet/socket set
  • A set of box wrenches
  • A turkey baster
  • Rags

Step 1 – Open hood

Open the hood. Once you're under there, you'll need to take off the cover of the old master cylinder.

Figure 1. Remove the top of the master cylinder.

Pro Tip

If you are looking to change out the old fluid, now would be a great time. However, you will need to access the brake calipers to perform a brake flush.

Step 2 – Drain old master cylinder

Use the turkey baster to suction out all the fluid from the master cylinder. Be cautious not to spill brake fluid on your car's paint as it is corrosive.

  • Figure 2. Use a suction device to remove the fluid. (Do not siphon it by mouth!)
  • Figure 3. Using a bottle to catch all the fluid is the usual method for this task.

Step 3 – Unbolt master cylinder

Unbolt the two bolts that hold the master cylinder to the brake booster. In addition, go ahead and put a rag under it and unbolt the brake line bolt running to it on the side.

Figure 4. Go ahead and take out the master cylinder.

Step 4 – Install new master cylinder

Installation is the reverse of removal. Install the new master cylinder and bolt the two bolts holding it to the brake booster.

Figure 5. Time to switch that master cylinder out.

Step 5 – Tighten brake lines

Take great care not to spill the fluid. Tighten up the brake line nuts with your box wrench first, this will be easier since it'll be loose and you can wiggle it around to position correctly before bolting it permanently to the brake booster assembly.

Now that it's back on the car, bleed it traditionally and you are done!

Figure 6. Back to normal braking with your new master cylinder installed.

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