2019-2024 Subaru Ascent Front vs Rear Brakes: What Wears First and What to Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2019-2024 Subaru Ascent the front brakes almost always wear out first, because weight shifts forward every time you stop and the front axle does most of the work. The rear brakes last longer but are not maintenance-free: the rear calipers also carry the electronic parking brake, so a rear pad job needs the parking brake retracted properly before anything comes apart. Plan on front pads more often, check the rears at every front job, and replace pads and rotors as a set on each axle.

How the Ascent Brake System Splits the Work

The Ascent uses disc brakes at all four wheels. There are no rear drums and no hand lever: the parking brake is electronic, applied with the switch on the center console. Subaru's own quick guide for the Ascent explains that you apply it by pressing the brake pedal and pulling up the switch, and that the brake system warning light and the switch indicator light up while it is set. The same guide describes Auto Vehicle Hold, which keeps the vehicle stopped at a light after you lift off the pedal, and X-MODE, which ties the engine, all-wheel drive and Vehicle Dynamics Control together for slippery surfaces. On current models Subaru adds Hill Descent Control to X-MODE, which uses the brakes to hold a steady crawl down steep grades.

When you brake, the vehicle's weight transfers toward the nose. That loads the front tires, so the front brakes are sized and proportioned to do the larger share of stopping. The Motorist Assurance Program puts the front share at about 70 percent of braking force on a typical vehicle. The rear brakes handle the rest and are deliberately held back so the rear tires do not lock first, which keeps the vehicle straight in a hard stop.

What Wears First, Front or Rear?

Do not assume the rears are fine just because the fronts went first. A three-row SUV that spends its life full of passengers and cargo, or towing, puts more load over the rear axle than a commuter car. Subaru rates the current Ascent for up to 5,000 pounds of towing when properly equipped, and a loaded trailer adds a lot of heat to all four corners. Measure the rear pads every time the fronts are done.

Symptoms and How to Tell Which End Is the Problem

• High-pitched squeal while driving that stops when you brake: often a pad wear indicator touching the rotor. Pull the wheels and look at pad thickness on both axles.
• Grinding: the friction material is gone and the backing plate is on the rotor. Wagner lists worn-out pads as a cause of pulling, rotor damage and high noise, with the fix being immediate pad replacement. Expect to need rotors too.
• Steering wheel shake when braking: points to the front rotors. A pulsation felt in the seat or only through the pedal on a gentle stop can come from the rear.
• Pulling to one side: a sticking caliper or uneven pad wear on one axle. Wagner ties tapered pad wear to distorted or sticking calipers.
• One wheel much hotter or dustier than the others: a dragging caliper. On the rear, check that the parking brake is fully releasing.
• Flashing brake warning light: on Subaru models with an electronic parking brake, a flashing brake system light signals a parking brake system fault rather than normal operation. Have it scanned before you order parts.

The quickest diagnosis is visual. With the wheels off, compare inner and outer pad thickness on each caliper, look at the rotor faces for deep grooves or a raised lip at the outer edge, and check that each caliper slides freely.

Common Causes of Fast or Uneven Wear

Wagner's disc brake troubleshooting chart lists the usual suspects, and they all apply to the Ascent:

• Uneven or worn rotors cause squeal and pedal pulsation and shorten the life of new pads. The fix is pads and rotors together.
• Sticking or dry caliper slides cause tapered or cracked pads. Clean and lubricate the slides, and service or replace the caliper if it binds.
• Contamination from grease, oil or brake fluid ruins pad friction. Contaminated pads must be replaced; cleaning does not save them.
• Heat from repeated hard use, such as long descents or towing, can glaze pads. Wagner notes light glazing usually clears with normal driving, but repeated overheating points toward a more heat-tolerant pad.

On the rear, a parking brake that does not fully release will wear the pads quickly and overheat the rotor. If the rear pads are wearing faster than the fronts, check the parking brake and caliper before blaming the pads.

The Fix: Which Parts to Buy for Each Axle

Buy by axle and by position. Front and rear pads for the Ascent are different shapes, so a front set will not fit the back.

• Front pads: 2019-2024 Subaru Ascent front ceramic brake pads by Power Stop or the Bosch front ceramic pads for the Ascent. Ceramic pads run quiet with low dust, which suits a family hauler.
• Rear pads: Bosch rear ceramic brake pads for the 2019-2024 Ascent or the Bendix rear ceramic pads.
• Rear pads and rotors together: the R1 Concepts rear brake kit for the Ascent.
• Both axles at once (2019-2021): the Detroit Axle front and rear brake kit.

For other options, browse our ceramic brake pads and brake rotors. Always confirm fitment by year and trim before ordering.

What to Replace at the Same Time

• Rotors: Wagner's guidance is that worn rotors should be replaced with the pads, because new pads on worn rotors can reduce stopping ability and wear out early. If the rotors are scored, lipped or below the minimum thickness stamped on them, replace them.
• Hardware: use the new abutment clips and shims supplied with the pads. Wagner points out that repeated heat cycles weaken old hardware, which leads to noise, uneven wear and binding. See our brake hardware kits if your pads do not include them.
• Caliper slides: clean and lubricate them with a brake-specific lubricant. Replace torn boots.
• Brake fluid: inspect the level and condition at the reservoir under the hood. Use only the fluid type printed on the reservoir cap or in your owner's manual, and follow the manual's replacement schedule.
• Both sides of the axle: always replace pads and rotors in left and right pairs so the vehicle stops straight.

How Hard Is the Job?

Front brakes: a standard job for a DIYer with basic tools, a jack, stands and a torque wrench. Remove the caliper, replace pads and hardware, swap the rotor if needed, and torque every fastener to the value in the factory service manual.

Rear brakes: harder because of the electronic parking brake. The parking brake motor is linked to the caliper piston, so the piston cannot simply be forced back with a clamp. The parking brake has to be released and the caliper put into its service or maintenance mode, either through the procedure in the factory service information or with a scan tool that supports it, before the pads come out. Forcing the piston can damage the actuator. After the job, cycle the parking brake as the service procedure directs and confirm the warning light goes out.

For either axle, pump the pedal to seat the pistons before you drive off, then bed in the new pads with a series of moderate stops before any towing or heavy loading.

Frequently Asked Questions

Why are my Ascent front brakes worn out but the rears still look good?

That is normal. Weight shifts forward when you brake, so the front brakes do most of the stopping and wear faster. Check the rears anyway every time the fronts are replaced.

Does the 2019-2024 Ascent have rear drum brakes?

No. It uses disc brakes on all four wheels, and the electronic parking brake works through the rear calipers rather than separate drum shoes.

Can I push the rear caliper piston back with a C-clamp?

Not until the electronic parking brake has been released and the caliper is in service mode. The parking brake mechanism is linked to the piston, and forcing it can damage the caliper actuator.

Should I replace rotors every time I replace pads?

Replace them if they are grooved, lipped, warped or under the minimum thickness stamped on the rotor. Putting new pads on worn rotors reduces stopping performance and shortens pad life.

Does towing change which brakes wear first?

Towing adds heat and load to all four corners and speeds up wear on both axles. The fronts still usually go first, but the gap narrows, so inspect the rears more often if you tow.

Are there brake recalls on the 2019-2024 Ascent?

NHTSA's recall database did not list a brake-system recall for 2019-2024 Ascent models when this guide was written. Check your VIN at nhtsa.gov before any repair, since recalls are added over time.

Sources

1. Subaru 2019 Ascent Quick Guide - electronic parking brake operation, Auto Vehicle Hold, X-MODE, brake fluid reservoir location
2. Subaru Ascent features - 5,000-pound towing rating and X-MODE Hill Descent Control
3. NHTSA / Subaru recall notice 18V-626 - a flashing brake system warning light indicates an electronic parking brake malfunction on Subaru EPB systems
4. NHTSA recalls by vehicle, Subaru Ascent - no brake-system recall listed for 2019-2024 Ascent
5. Motorist Assurance Program: Which Brakes Go Bad First - front brakes handle about 70 percent of braking force and wear first
6. Wagner Brake: Signs of Worn Brake Pads - causes and fixes for uneven, tapered, glazed and contaminated pads
7. Wagner Brake: Four Tips for Replacing Brake Pads - replace worn rotors with pads and install new hardware