2010-2013 Infiniti EX35 Brake Noise: Squeal, Grinding and Pulsation Causes

By Core Brake Parts Tech Team — Circleville, OH warehouse

Most brake noise on a 2010-2013 Infiniti EX35 comes down to three things: a high-pitched squeal from worn pads or tired pad hardware, a grinding sound from pads worn to the backing plate or debris trapped at the rotor, and pedal or steering pulsation from rotor thickness variation. The EX35 runs discs at all four corners, so any of these can come from the front or the rear, and the fix is usually pads, hardware and rotors on the axle that is making the noise.

How the EX35 Brake System Is Built

The EX35 is a compact luxury crossover built on a rear-drive platform, offered in rear-wheel drive and Intelligent All-Wheel Drive versions. According to Infiniti's own 2010 technical specifications sheet, it uses four-wheel power-assisted disc brakes with a four-channel, four-sensor ABS, Electronic Brake force Distribution (EBD), Brake Assist, and Vehicle Dynamic Control with traction control as standard equipment.

Two details matter for noise. First, the rear rotor is large in diameter but thin, which makes it quick to rust and pick up uneven pad deposits when the vehicle sits, and a thin rotor has little material to machine away. Second, the EX35 is heavy for its size, close to two tons in AWD trim, and the front axle carries a little over half of that weight, so the front pads and rotors do most of the work and run the hottest. Always confirm the exact parts for your VIN, since drive type and build date can affect part numbers.

Squeal: What It Means and How to Diagnose It

A squeal is a high-frequency vibration between the pad, rotor and caliper that the chassis turns into sound. On an EX35 that has not had brakes in a while, start with the simplest cause: pad wear. Many pads carry a metal wear tab that touches the rotor once the friction material gets thin. Power Stop notes that these mechanical indicators start to contact the rotor when roughly 1/8 to 1/4 inch of pad remains, producing a steady squeal while driving.

If the pads still have plenty of material, check these instead:

• Tired or missing pad hardware. Spring-loaded abutment clips lose tension over time and let the pad vibrate in the bracket. Wagner and Power Stop both recommend replacing clips, springs and pins with the pads, not reusing the old set.
• Dry or seized slide pins. A caliper that cannot float evenly holds one pad against the rotor, which causes noise and uneven wear.
• Rust on the rotor face or the hub. A light squeal for the first few stops after rain or a wash is normal as pads scrub rust off. Rust scale between the rotor hat and the hub face is not normal and should be cleaned off during any rotor job.
• Glazed pads and rotors. Heat from hard braking can polish both surfaces smooth. Glazing reduces friction as well as causing noise, so it is a performance issue, not just an annoyance.
• Damaged or missing shims. Shims damp the vibration before it reaches the caliper and knuckle. Brake and Front End explains that multi-layer shims use viscoelastic material to absorb vibration and add mass that settles the pad down, and that a shim left out of the job does nothing.

Grinding: Stop Driving and Inspect

A grinding or scraping sound is more urgent than a squeal. The most common cause is metal-to-metal contact: the pad friction material is gone and the steel backing plate is cutting into the rotor. At that point the rotor is almost always damaged and must be replaced along with the pads, and a caliper piston that has extended too far can be harmed too.

The second common cause is a stone or piece of debris trapped between the rotor and the dust shield. That sound is usually constant, is present even without the brakes applied, and can appear suddenly after driving on gravel. Pull the wheel, remove the debris, and look at the rotor face for a scored groove.

On an EX35, also pin down which end the noise comes from. Because the rear rotors are thin, a rear pad that wears to the backing plate can ruin them quickly. Vehicles with EBD and stability control also lean on the rear brakes to balance the car, so do not assume the rears are fine just because the fronts were done recently.

Pulsation and Vibration: Rotor Thickness, Not Warped Rotors

If the pedal pulses or the steering wheel shakes when you slow from highway speed, the rotors are usually blamed as warped. Brake and Front End explains that rotors do not really warp. What drivers feel is disc thickness variation: as thicker and thinner sections of the rotor pass through the caliper, the piston is pushed in and out, and that movement comes back through the pedal. Thickness variation usually starts from lateral runout, where one part of the rotor rubs the pad more often, and from uneven pad deposits on rotors that were never properly bedded.

Their figures show how small the tolerances are: new rotors typically run out around 0.001 inch or less, the upper limit is about 0.004 inch, and some sensitive vehicles pulse with as little as 0.0015 inch. That is why a rotor that looks fine can still cause a shake, and why hub cleanliness matters so much: rust scale on the hub face tilts a new rotor and puts runout right back in.

Diagnose the axle before buying parts. A shake felt mainly in the steering wheel points to the front rotors. A pulse felt mostly in the pedal and seat, with a steady steering wheel, often points to the rear. Worn wheel bearings, tire problems and unevenly torqued lug nuts can mimic rotor pulsation, so check those too, and always tighten the wheels in a star pattern to the factory value with a torque wrench, not an impact gun.

The Fix: Parts and What to Replace Together

For a squeal or pulsation on one axle of an EX35, the durable repair is:

1. New pads with fresh shims, from our brake pads selection or the lower-dust ceramic brake pads collection.
2. New rotors, since the rear rotors are thin and pulsation means thickness variation. Browse replacement brake rotors.
3. A new brake hardware kit with abutment clips and pin boots.
4. Cleaned and lubricated slide pins, cleaned pad contact points on the bracket, and a clean hub face.
5. A proper break-in. Wagner describes a bedding procedure of 20 gradual slowdowns from 50 mph to 20 mph with light pressure and about 30 seconds between them; follow the instructions that come with your pads.

For owners who want more bite from the rear, we carry Hawk HPS 5.0 rear brake pads for the 2010-2013 EX35. Hawk describes HPS 5.0 as a Ferro-Carbon street performance compound designed for standard iron rotors. It suits drivers who want firmer pedal feel; a daily commuter focused on quiet operation will usually be happier with a ceramic pad.

If a caliper is sticking and the slide pins are not the cause, look at brake calipers, and check the brake fluid condition while you are there.

How Hard Is the Job?

Pads and rotors on the EX35 are a moderate DIY job with basic hand tools, jack stands, a torque wrench and a caliper piston tool. The front is straightforward. The rear takes more care: a rotor that has rusted to the hub may need penetrating oil and patience, and the parking brake must be fully released before the rotor will slide off. Do both sides of an axle at once, never a single corner. For torque values and parking brake adjustment, follow the factory service manual or have a shop finish the job.

Frequently Asked Questions

Why do my EX35 brakes squeal only in the morning?

A short squeal for the first few stops after the vehicle sits overnight or in the rain is usually surface rust being scrubbed off the rotors. If it fades within a few stops it is normal. If it continues all day, check pad thickness and hardware.

Does the EX35 have rear disc brakes or drums?

Disc brakes. Infiniti's 2010 specifications list a 12.6-inch vented front disc and a 12.1-inch rear disc, with four-channel ABS on all four wheels.

Can I resurface my EX35 rotors instead of replacing them?

Only if they stay above the minimum thickness stamped on the rotor after machining. The rear rotors are only about 0.6 inch thick new, so there is little to remove. Replacement is often the better repair.

Why do my new brakes pulse after only a few thousand miles?

The usual causes are rust left on the hub face, uneven lug nut torque, or pads that were never bedded in. All of these create thickness variation that you feel in the pedal.

Should I change front and rear pads at the same time?

Not necessarily. The front usually wears faster. Measure both axles and replace whichever is thin, but always replace both sides of an axle together.

Sources

1. Infiniti 2010 EX35 Technical Specifications, Features and Options - front and rear rotor sizes, ABS, EBD, Brake Assist, VDC, curb weights and weight distribution
2. Wagner Brake - Brake System Noise Troubleshooting - vibration as the source of noise, hardware and hub cleaning, bedding procedure
3. Brake and Front End - How to Fix Brake Noise - causes of squeal, grinding, clunk and pulsation
4. Brake and Front End - Brake Rotors and Pads: 12 Myths Debunked - thickness variation versus warping, runout tolerances
5. Power Stop - Causes and Solutions for Squealing Brake Pads - wear indicator thickness, clips, lubrication, glazing
6. Brake and Front End - Brake Shimology - how shims damp brake noise
7. Hawk Performance - HPS 5.0 - HPS 5.0 compound type and intended use