Stock Wrangler Brake Systems & How to Upgrade Them

Most present-day Jeep braking systems run off a hydraulic fluid system. In basic terms, when you push the brake pedal an arm pushes a piston into the master cylinder. The piston’s function is to compress the hydraulic braking fluid and create pressure in the brake lines, which are connected to the brake calipers. The calipers themselves have a piston that pushes on a brake pad. The brake pad then creates friction along the face of the brake rotor, slowing it down to an eventual stop.

Older Wranglers generally have rear drum brakes that utilize the same hydraulic fluid and compression method as disc brakes, but instead of brake calipers and rotors, the drum itself is connected to the rear axle/hub. The wheel is then bolted onto the drum. When the brake pedal is pressed and the fluid is compressed, the pistons in the drum’s wheel cylinder moves outward in opposing directions, pushing the outer brake shoes. This push allows the curved brake shoe to contact the inner wall of the drum. The contact then creates friction, similar to a disc brake and results in the same reduction in speed and eventual stopping of the Jeep. Drum brakes however are inefficient and problematic. Return springs designed to bring the brake shoe back into position when not in use are often rusted and fail to bring the brake shoe back, resulting in continued friction or locking/seizing of the rear brakes. In addition, the design of a drum brake isn’t as powerful as disc brakes and has very limited upgrade options.

If your Wrangler is an older model that utilizes drum brakes, there are several conversion kits available that upgrade them to a modern disc brake system. The Teraflex rear disc brake conversion kit comes with everything you’ll need to upgrade the rear brakes of your Jeep. The kit includes a set of new rotors, calipers, brake pads, and all the hoses needed to switch over from a drum brake system.

The upgrade of a rear drum brake system to a disc brake system will provide a more efficient, stronger rear brake. Disc brakes utilize calipers positioned along the outer edge of the rotor. This allows for the maximum amount of leverage which results in a stronger level of resistance. Imagine trying to remove a nut with a wrench. If you grab the wrench close to the center it will require more force and energy to move the nut. Grabbing the wrench farther out creates more leverage and requires less energy to move the nut. The same theory applies with the rotors and calipers found on disc brakes.

Applying the same principles of leverage, factory disc brake systems can also be upgraded to a larger overall rotor. This utilizes the leverage theory, by providing a larger footprint that pushes the caliper out further, resulting in greater braking power that is much more efficient. The Teraflex Big Brake kit easily upgrades the factory front disc brakes to a larger 13.3 slotted rotor, compared to the factory front rotors which are around 12.5-inches. The increase in size provides more braking surface and allows the caliper to sit out further from the center of the wheel hub.

The slotted design of these rotors, and most aftermarket rotors, are designed to dissipate heat and gas buildup caused from the friction of the brake pad when it’s compressed against the face of the rotor. In addition, the calipers themselves are also upgraded in this kit. They have two pistons instead of the single piston design on the factory caliper. The dual pistons provide more compression of the brake pad against the face of the rotor, resulting in stronger braking power and resistance. Due to the increase in rotor size, this larger brake system does, however, require at least 17” wheels.

In addition to larger rotors and multi-piston calipers, there are several other brake system components that can be upgraded. The Teraflex Master Cylinder with over-sized bore basically allows you to run more brake fluid. Running more brake fluid is sometimes required if you plan on running a larger brake system with a multi-piston caliper. Often multi-piston calipers require a larger volume of fluid to properly compress the brake pad against the larger rotor. This new master cylinder will provide about 14% more brake fluid.

Delivering the fluid efficiently is done through the brake lines. The factory brake lines are generally made of rubber. The problem occurs during heavy braking. The fluid heats up and the rubber starts to flex during compression. The flexing causes a loss or fading of braking power. A stainless brake line like the Rough Country front stainless brake line helps address this problem by providing an outer layer of stainless steel mesh. This steel mesh prevents excessive flexing during fluid compression and helps deliver the fluid and pressure more efficiently, resulting in less fading during excessive braking. It’s also important when lifting the height of your Jeep to keep the length of your brake lines in mind. Synergy extended front and rear brake lengths provide the extra length needed for Jeeps running a lift.

As discussed in this information guide, the braking system of your Jeep is a critical component that ensures you can properly control your vehicle. It’s important to considering braking as a vital upgrade anytime you modify your Jeep’s tire size or engine performance. Increasing braking power is always a good idea, but especially when your Jeep has been modified or encounters extreme conditions. In addition, regular maintenance and inspection of your braking system is important to ensure good overall braking power while on the road or on the trail.