2000-2004 Toyota Avalon Front vs Rear Brakes: What Wears First and What to Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2000-2004 Toyota Avalon, the front brakes almost always wear out first. The front discs do most of the stopping on this front-heavy V6 sedan, so front pads usually need replacing more often than the rears. The rear discs last longer, but the Avalon also has a small drum parking brake built into each rear rotor, and people forget to check it.

How the Avalon Brake System Is Laid Out

The second-generation Avalon (2000-2004) has disc brakes at all four wheels. Brake parts makers list the front rotor at 275 mm (10.83 in.) and vented, with five lug holes. The rear rotor is a different part with its own size, and its center hat is also the drum for the parking brake, so front and rear rotors are never interchangeable.

That parking brake is a drum-in-hat design. Inside each rear rotor hat, a pair of small shoes presses outward against the inner drum surface when you set the brake. Toyota's own parts catalog lists the parking brake shoe assemblies (for example 46540-07010 and 46550-07010) for 1995-2004 Avalon models. Those shoes hold the car when it is parked. They do nothing during normal stops, so they wear slowly. But they can rust, glaze or go out of adjustment.

Why the Front Brakes Wear First

When you brake, the car's weight pitches forward onto the front tires. That gives the front tires more grip and takes grip away from the rears. Engineers size and proportion the system to match, and this front-rear split is called brake bias. The Motorist Assurance Program, an auto-repair industry group, puts the front brakes' share at about 70% of the braking force on a typical vehicle. The Avalon carries a transverse V6 over the front axle, so it follows the same pattern.

Front pads handle more heat and more friction every stop, so they wear out sooner. On most Avalons the front pads and rotors need replacing before the rears. A reasonable plan is to replace front pads on their own schedule and inspect the rears every time the fronts are done.

A car whose rear pads wear faster than its fronts has a problem, not a quirk. The usual causes are a sticking rear caliper slide pin, a seized caliper piston, or a parking brake that never fully releases. Any of these drags a rear pad against the rotor all the time.

Symptoms and How to Tell Front From Rear

• High-pitched squeal or screech when braking. This is usually the pad wear indicator, a small metal tab that touches the rotor when the friction material gets thin. Freeway Toyota describes it as a distinctive metallic screeching when you apply the brakes. Stand beside each wheel while a helper creeps the car forward and brakes lightly to find which corner it comes from.
• Steering wheel shake when braking at highway speed. This points to the front rotors. Uneven rotor thickness shows up through the steering.
• Pulsation in the pedal or seat, with a steady steering wheel. This more often points to the rear rotors.
• Grinding. The pad is down to its backing plate and is cutting the rotor. Stop driving on it. At this point the rotor has to be replaced.
• One rear wheel hot after a drive, or the car rolls sluggishly. This points to a dragging rear caliper or a parking brake that is stuck on.
• Parking brake lever pulls up too far or will not hold on a slope. The rear drum-in-hat shoes need adjustment or replacement.
• Low fluid in the master cylinder reservoir. Freeway Toyota notes that low brake fluid means either a leak or worn brakes. Fluid level drops a little as the pads wear, but a sudden drop means you should look for a leak.

The Fix: Which Parts to Replace

Front brake job

For worn front pads, replace the pads and either resurface or replace the rotors. Many owners simply replace the rotors, since a new rotor starts at full thickness. Measure the old rotor. If it is at or under the minimum thickness stamped on the casting, replace it; the front rotor spec published by brake-parts makers for this car is 26 mm. Browse brake pads and brake rotors. If you want low dust and quiet stops on a daily driver, ceramic brake pads are the usual choice.

Rear brake job

For the rears, replace the pads and rotors the same way. With the rotor off, check the parking brake shoes and the hardware inside the hat. Look for lining that is thin, cracked, soaked in grease or brake fluid, or coming away from the shoe. Look for broken or stretched springs. Replace the shoes if they are worn down close to the metal. After installing new rotors, adjust the parking brake shoes through the access hole to the factory specification before you adjust the cable.

Doing all four at once

If both ends are worn, a matched front and rear kit saves a second trip under the car. We carry a 2000-2004 Toyota Avalon front and rear brake kit with rotors and pads for all four corners. Kits like this usually include pads, shims, rotors and fresh hardware clips. Power Stop's stock replacement kit, for example, includes ceramic pads, shims, rotors, stainless hardware and high-temperature brake lubricant.

What to Replace at the Same Time

• Hardware clips and shims. Worn anti-rattle clips cause noise and uneven pad wear. See brake hardware kits.
• Caliper slide pins and boots. Clean them, lubricate them with high-temperature brake grease, and replace any torn boot. A seized pin is the top reason one pad wears faster than the other.
• Calipers. Replace a caliper that leaks at the piston seal, has a piston that will not push back, or drags after cleaning. Replace them in pairs across the axle. See brake calipers.
• Brake hoses. On a car this old, check the rubber flex hoses for cracks and bulges. See brake hoses.
• Brake fluid. The Avalon uses DOT 3 fluid, and Freeway Toyota specifies Toyota Heavy Duty Brake Fluid DOT 3 when the system is flushed. Brake fluid absorbs moisture over time, and the moisture corrodes metal parts and seals. A 20-year-old car that has never had a flush is overdue.

How Hard Is the Job?

A front pad and rotor job on the Avalon is a good first brake job for a careful DIYer with a jack, jack stands, a C-clamp or piston tool, and a torque wrench. The caliper comes off with two slide bolts, the bracket comes off with two larger bolts, and the rotor slides off the hub. Rust at the hub face can make it stick. Tighten every bolt, and the wheel lug nuts, to the values in the factory service manual.

The rear is similar for the pads and rotor, with one extra step. If the rotor will not come off, back off the parking brake shoe adjuster through the access hole first. Never pry hard on a rotor that is held by the shoes. Budget extra time on the rear the first time you do it.

After any pad or rotor change, pump the pedal until it is firm before you drive. Then bed in the new pads with a series of moderate stops from moderate speed, with no hard stop to zero. Follow the pad maker's break-in procedure. Power Stop, for one, requires its break-in procedure for its return guarantee.

There are no open recalls on the 2000-2004 Avalon's service brakes in NHTSA's database. The only recall for these model years covers the steering lock bar. Still, enter your VIN at nhtsa.gov to check your own car.

Frequently Asked Questions

Does the 2000-2004 Toyota Avalon have rear disc brakes or drums?

It has rear disc brakes. It also has a small drum parking brake inside each rear rotor hat. So you have both rear pads and parking brake shoes, but the shoes only work when the parking brake is set.

Should I replace front and rear brakes at the same time?

Only if both are worn. The fronts usually wear first. Replace pads and rotors in pairs across an axle, always both sides. Inspect the rears whenever you do the fronts, and do all four only when the rears are also near their limit.

Why are my rear pads wearing faster than the fronts?

On an Avalon that is not normal. Check for a sticking rear caliper slide pin, a seized piston, or a parking brake that is not fully releasing. Also check the rear shoes for correct adjustment.

What brake fluid does the Avalon use?

DOT 3. Toyota dealers use Toyota Heavy Duty Brake Fluid DOT 3 when they flush the system. Do not mix in DOT 5 silicone fluid.

Can I just replace the pads and keep the rotors?

You can if the rotors are above minimum thickness, smooth, and free of pulsation. If they are grooved, warped, or at the limit, replace them. New pads on bad rotors will be noisy and will not bed in properly.

Sources

1. QTEAUTO - Front rotors for 1995-2004 Toyota Avalon - 275 mm vented front rotor, 26 mm minimum thickness, 5 lug holes
2. Toyota Parts Deal - Genuine Toyota Avalon parking brake shoe - drum-in-hat parking brake shoe part numbers for 1995-2004 Avalon
3. Motorist Assurance Program - Which brakes go bad first - front brakes handle about 70% of braking force and usually wear first
4. Freeway Toyota - Brakes, brake pads and brake rotors - wear indicator screech, low fluid warning, Toyota DOT 3 brake fluid, fluid absorbs moisture
5. Power Stop - Stock replacement brake kit - kit contents and required break-in procedure
6. NHTSA - Recalls for the Toyota Avalon - only recall for 2000-2004 is steering lock bar (10V345000), none on service brakes