Inspired by the 1991 release of the Explorer Eddie Bauer edition -- a luxury-style SUV -- Jeep released its own luxury SUV, the Grand Cherokee, in 1993. The 1998 Grand Cherokee came standard with front disc brakes and rear drum brakes, just as most other vehicles did throughout the 1990s. As an optional feature, buyers could add in the safety and stability of four-wheel disc brakes. Knowing and understanding the main components of the Grand Cherokees rear disc brake system is the first step in learning to replace the brakes.
Brake Hoses
The 1998 Grand Cherokees rear disc braking system starts with its hoses; each side of the Grand Cherokee has one brake hose. These hoses are made of rubber and carry the pressurized brake fluid from the brake lines to the brake calipers.
Any time you perform a rear brake job, you must inspect these hoses for any visual defects, including: spongy feeling, cracks, splits or breaks. If any defects exist, replace the hoses immediately. If you remove the brake hoses for any reason, always tighten the banjo bolt (the one that secures the hose to the caliper) to 23 foot-pounds of torque and replace the two brass sealing washers.
Brake Caliper
The main hydraulic components of the 1998 Grand Cherokees rear brakes are the rear calipers. These components hold the brake pads, as well as squeeze the pads together to bring the SUV to a stop. When replacing the brake pads, always inspect the calipers for leaks or a damaged dust boot.
After removing the 1998 Grand Cherokees caliper for any reason, always torque its retaining bolts to between 7 and 15 foot-pounds.
Brake Pads
The 1998 Grand Cherokees brake pads are the main friction components of the rear brake system. These pads have a thick layer of friction material, which typically contains metallic fibers mixed in with organic elements, adhered to a metal backing plate. The 1998 Grand Cherokees brake pads have small metal clips that secure them into the caliper, eliminating the need for a separate caliper bracket (the bracket is part of the rear spindle). Over time, the friction material wears down and loses its effectiveness (this is the most common cause for brake repair).
If you allow the friction material to get so thin that the metal backing plate contacts the rotor, you are all but guaranteed to need to replace the rotors, as well.
When replacing brake pads, always replace the pad slippers (the metal shims above and below the pads) and the shims on the rear of the pads. These are so important that most brake pad manufacturers include them with the new pads. It is also best to apply a thin coating of disc brake grease on the rear of the pads to keep vibration noises to a minimum.
Rotors
The brake rotors on the rear of the 1998 Grand Cherokee are the large, metal discs that the pads press against to bring the SUV to a halt. Once you get the pads and calipers off, the rotor just pulls off the rear hub.
This component wears out like the pads do, but at a slower rate than the pads. A good rule of thumb is to replace the rotors any time they show any sign of wear, including: cracks, deep grooves, signs of brake pad grinding or a mirror-like shine. If you have a micrometer, you can also check the rotors thickness. If the 1998 Grand Cherokees rotor is thinner than 0.419 inches, it is time to replace it.
Parking Brake Shoes
Unlike most vehicles, the 1998 Grand Cherokee uses parking brake shoes to hold the vehicle still when you engage the parking brake. Most vehicles use a ratcheting caliper and, therefore, require a special tool to retract the caliper piston during brake pad replacement.
On this system, the parking brake shoes press on a small drum in the center of the rear rotor to hold it in place. The shoes adjust automatically, but sometimes the automatic adjuster fails, therefore you must adjust the shoes manually, using the star-shaped adjuster wheel that is accessible via the rotor backing plate.
