2018-2023 Audi Q5 Brake Noise: Squeal, Grinding and Pulsation Causes

By Core Brake Parts Tech Team — Circleville, OH warehouse

Most brake noise on a 2018-2023 Audi Q5 comes from a short list of causes that Audi itself documents: pads or rotors near their wear limit, pads that were never properly bedded in, rust or pad deposits on the rotor face, and grit trapped between pad and rotor. On this generation specifically, there are also two known noises: a loose front pad retaining pin that rattles, and a brake booster boot that squeaks when you press the pedal. Grinding usually means metal-to-metal wear, and a pulsing pedal usually means uneven rotor thickness, not a truly warped rotor.

This guide walks through each noise the way a brake tech would: what it sounds like, what Audi's own service bulletins say causes it, and which part actually fixes it.

How the Q5 Brake System Is Laid Out

The second-generation Q5 (and SQ5) that launched for the 2018 model year uses disc brakes at the front and an electronic parking brake at the rear. The rear parking brake is applied by an electric motor rather than a cable, so rear pad work on this vehicle needs the parking brake put into service mode with a capable scan tool before the caliper piston can be retracted. Forcing the piston back without doing that risks damaging the actuator.

Up front, the calipers use pad retaining pins, and Audi has issued a bulletin about those pins working loose. At the pedal, a brake servo (booster) assists your foot, and that booster has its own documented noise. Knowing which of these three areas the sound comes from is the first step in any diagnosis, and Audi's general brake noise bulletin says exactly that: locating the noise is critical to fixing it.

Squeal and Squeak: The Most Common Complaints

Audi's brake noise analysis bulletin (TSB 2034181, which applies to all Audi models from 2012 through 2023, including the Q5) lists the most common causes of squealing and squeaking:

• Pads or rotors close to or below their wear limit. Worn friction material and thin rotors are the leading source of squeal.
• New pads or rotors that were not properly embedded. Audi calls bedding-in "embedding." Skipping it leaves an uneven layer of friction material on the rotor.
• Debris such as small stones, grit, road salt or sand between the rotor and pad.
• Rust on the rotor face, typically after the vehicle has sat unused for a long period.
• Grooved rotors.
• Chemical contamination from wheel or tire cleaner sprayed directly onto the rotor, which shows up as discoloration and small spots.
• Pad marks, where pad material transfers onto the rotor after the vehicle has been parked for long periods in wet or snowy conditions.

The same bulletin lists aftermarket pads or discs as a possible cause. In practice, that is a quality and fit question: pads with poor shims or the wrong friction formula for the rotor can sing, while a quality ceramic pad with proper shims and correctly lubricated contact points is typically quiet. Brembo's maintenance guidance makes the same point from the parts side: anti-noise shims must be applied correctly and never reused, worn caliper springs must be replaced and positioned correctly, and the caliper bracket contact surfaces need anti-noise grease.

For a Q5 that squeals only in the first few stops on a damp morning and then goes quiet, surface rust is the usual cause and it is harmless. A squeal that is constant, gets louder over weeks, or is present on every stop points to wear, glazing, or a hardware problem that needs inspection.

The pedal squeak that is not the brakes at all

If you hear a squeak when you press the brake pedal, it may not be coming from the wheels. Audi TSB 2067321 covers 2018-2021 Q5 and SQ5 models (plus 2021 Q5 Sportback and SQ5 Sportback, excluding plug-in hybrids) where squeak noises come from the brake servo unit's rubber boot. Audi introduced an improved boot gradually in the first quarter of 2021, and the bulletin's repair is replacement of the brake servo unit. If your Q5 is in that range and the noise follows the pedal rather than the wheels, have a dealer check it against that bulletin before you buy pads you may not need.

Rattles Over Bumps

A light metallic rattle from the front axle over rough pavement is a known Q5 complaint. Audi TSB 2063040 covers 2018-2022 Q5 and SQ5 models with front disc brakes: the front caliper pad retaining pins can work loose from vibration and move out of position. The bulletin's fix, performed when pads are replaced, is to seat the retaining pin and apply a drop of locking fluid to the pin's barrel spring so it stays put.

That makes the retaining pins and anti-rattle hardware worth checking at every front pad change. If the pins, springs or clips are corroded or distorted, replace them with a fresh brake hardware kit rather than reusing tired parts.

Grinding: Stop Driving on It

Grinding is different from squeal. A steady, harsh grinding sound under braking usually means the friction material is gone and the steel backing plate is contacting the rotor, or a stone is trapped between the pad and rotor or behind the dust shield. A trapped stone often makes a scraping sound even when you are not braking, and it can come and go.

Metal-on-metal grinding scores the rotor quickly, so what could have been a pads-only job becomes pads and rotors. Grooves are one of the noise causes Audi lists, so a rotor that has been ground into will keep making noise even with new pads. If you hear grinding:

1. Pull the wheel and look at pad thickness through the caliper opening and at the rotor face.
2. If the pad lining is worn to the backing plate or the rotor is deeply grooved, replace the rotors and pads together as an axle set.
3. If the pads are fine, check for a stone or a bent dust shield touching the rotor.

Treat a brake pad warning on the dash as a prompt to inspect soon, before grinding starts. If your pads use an electronic wear sensor, replace the sensor whenever the pads it monitors are replaced, since a sensor that has been worn through will not reset.

Pulsation: Why the Pedal Pulses

A pedal that pulses, or a steering wheel that shakes under braking, is usually blamed on "warped rotors." Brake friction makers describe the real mechanism differently. Ferodo's technical guidance names three causes of brake judder: hub and disc runout (often from rust or dirt on the hub face preventing the rotor from sitting flat), severe overheating, and disc thickness variation. Thickness variation develops when pads are not bedded in, when a caliper sticks, or when pad material is deposited unevenly on the rotor.

Brembo's maintenance guidance gives concrete limits: rotor runout measured on the hub should normally not exceed 0.10 mm, and hub runout should not exceed 0.050 mm. Both brands stress cleaning rust and dirt off the hub-to-rotor mating surface before fitting a rotor, because even a thin layer of corrosion tilts the rotor and starts the cycle of uneven wear.

The Fix: Parts and Procedure That Keep It Quiet

For a Q5 with worn front brakes, the lasting fix is quality pads, fresh rotors where they are worn, grooved or out of spec, and clean, lubricated hardware. We carry 2018-2023 Audi Q5 front ceramic brake pads from Bendix, and you can browse more options in our ceramic brake pads and brake pads collections. Always confirm your specific brake package, since Audi builds the Q5 with more than one front brake system depending on engine and options.

Replace at the same time:

• Rotors if they are at or near minimum thickness, grooved, or causing pulsation. Brembo recommends always replacing pads when changing discs.
• Wear sensors on the axle being serviced, where fitted.
• Anti-rattle springs, clips and retaining pins if they are corroded or bent, plus fresh shims.
• Brake fluid, if it is due by age per your maintenance schedule. Use the fluid specification printed in your owner's manual or on the reservoir cap.

Procedure points that prevent noise from coming back:

• Clean the hub face down to bare metal before fitting a rotor.
• Clean and lightly lubricate the pad contact points on the caliper bracket with the correct brake paste, keeping it off the friction surfaces.
• Install pads in the correct position and direction; many Audi pads are marked for side and inner or outer position.
• Torque caliper and wheel bolts to the values in the factory service manual.
• Bed the brakes with a series of moderate stops and cool-down driving between sets. Avoid hard stops while the new parts bed in; Brembo and Ferodo both advise easy braking for the first few hundred kilometers.

How Hard Is the Job?

A front pad and rotor job on a Q5 is a moderate DIY task for someone with a torque wrench, jack stands and basic hand tools. Rear pads are harder because of the electronic parking brake: without a scan tool that can put the system into service mode, leave the rears to a shop. Anything involving the brake booster or master cylinder is a dealer or professional job.

One safety note for 2018-2019 owners: Audi recall 47O9 (NHTSA 19V277) covered certain 2018-2019 Q5 and SQ5 vehicles whose brake master cylinder casting could be too short, which could cause a sudden loss of hydraulic braking with the pedal going to the floor. The dealer inspects and, if needed, replaces the master cylinder free of charge. That recall is about brake performance rather than noise, but if your Q5 falls in that range, confirm with a VIN check that it was completed.

Frequently Asked Questions

Why do my Audi Q5 brakes squeal in the morning and then stop?

A thin layer of rust forms on the rotor faces overnight, especially in damp weather. The first few stops scrub it off and the noise goes away. Audi lists rust on the rotors as a common noise cause; it is only a concern if it persists after the brakes are warm.

Is it normal for a Q5 to rattle from the front wheels over bumps?

It is a known issue. Audi TSB 2063040 covers 2018-2022 Q5 and SQ5 front pad retaining pins that work loose from vibration. The fix is to reseat the pin and apply locking fluid to its spring, usually done during a pad change.

My brake pedal squeaks when I press it. Do I need new pads?

Probably not. On 2018-2021 Q5 and SQ5 models, Audi TSB 2067321 traces pedal squeak to the brake servo unit rubber boot. Have the noise located before replacing any friction parts.

Do I have to replace rotors every time I replace pads on a Q5?

Not always, but rotors that are at their wear limit, grooved, or causing pulsation should be replaced with the pads. Worn rotors are one of the most common causes of noise on new pads according to Audi's own bulletin.

Can I replace the rear pads without a scan tool?

The Q5 uses an electronic parking brake, so the rear calipers need to be put into service mode before the pistons are retracted. Doing it without the proper tool risks damaging the parking brake actuator.

Are my rotors warped if the pedal pulses?

Usually the rotor has uneven thickness or uneven pad deposits rather than true warping. Hub runout from rust on the mounting face is another common cause, so clean the hub when fitting new rotors.

Sources

1. Audi TSB 2034181/21: Brake noise analysis and handling (NHTSA) - noise causes, applies to all Audi models 2012-2023
2. Audi TSB 2063040/1: Front axle rattle, retaining pins (NHTSA) - 2018-2022 Q5/SQ5 loose retaining pins and locking fluid fix
3. Audi TSB 2067321/4: Brake servo unit noisy when pressing pedal (NHTSA) - 2018-2021 Q5/SQ5 booster boot squeak
4. Audi Safety Recall 47O9 / NHTSA 19V277 owner letter - 2018-2019 Q5/SQ5 master cylinder casting; electronic parking brake
5. Brembo: Noises and vibrations - runout limits, shims, springs, anti-noise grease, bedding-in
6. Ferodo: Brake judder technical tip - runout, overheating and disc thickness variation as judder causes