2014-2020 Infiniti Q50 Front vs Rear Brakes: What Wears First and What to Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2014-2020 Infiniti Q50, the front brakes almost always wear out first. The fronts do most of the stopping on every car, and the Q50 is no exception, so front pads usually need replacing well before the rears. The rears still wear, though, and the rear rotor also holds the parking brake shoes, so they need their own check at every service.

How the Q50 Brake System Splits the Work

Every Q50 in this generation uses four-wheel disc brakes. Infiniti's owner's manual describes self-adjusting disc brakes that adjust every time the pedal is applied, plus a Brake Assist function that adds braking force when the pedal is pressed hard in an emergency. Anti-lock braking and Vehicle Dynamic Control (VDC) sit on top of that hydraulic system.

When you brake, the car's weight shifts forward. That loads the front tires and unloads the rears, so the front axle can do more of the work without locking up. The Motorist Assurance Program, an automotive repair industry standards group, puts the front share at about 70 percent of total braking force on a typical vehicle. That is why front pads and rotors wear faster on nearly everything with a steering wheel, and a front-heavy sport sedan with a V6 or turbocharged four up front follows the same pattern.

The rear brakes on the Q50 do one extra job: the parking brake. The Q50 uses a foot-operated parking brake pedal, and the manual refers to parking brake shoes and drums, meaning a small drum-style shoe setup built into the center (the "hat") of each rear rotor. That matters when you replace rear rotors, as covered below.

Brake packages are not all the same

The Q50 was sold with more than one brake package. Base, Premium and Hybrid trims used the standard brakes, while some Sport-trim cars came with a larger performance brake package. Aftermarket fitment data for the standard system lists a 12.6 inch vented front rotor and a 12.1 inch vented rear rotor for 2014-2017 cars, and one 2017 Sport variant with 2-piston front calipers shares those parts. Cars with the larger performance brakes take different rotors and pads. Before you order anything, look through the wheel spokes and count the front caliper pistons or check the caliper for a brand name, and confirm the fitment notes on the part.

Front vs Rear: What Wears and When

The inspection intervals come from Infiniti's own maintenance schedule in the Q50 owner's manual. Severe conditions include long periods of idling or low-speed driving, dusty roads, rough or salt-covered roads, and using a car-top carrier. If most of your driving is stop-and-go city traffic, treat your car as severe service and look at the brakes twice as often.

Do not assume the rears are fine just because the fronts wore first. Stability control and traction control can apply individual rear brakes, and a sticking rear caliper slide or a seized parking brake can wear a rear pad down faster than expected. The only way to know is to measure both axles.

Symptoms and How to Tell Which End Needs Work

• High-pitched scraping when braking: Infiniti states the Q50's disc brake pads have audible wear warnings. When a pad needs replacing, it makes a high-pitched scraping sound, first only when the pedal is pressed. As wear continues, the sound is heard all the time, even off the brake. Infiniti's advice is to have the brakes checked as soon as possible once you hear it. Listen with a window down in a quiet parking lot: the sound is usually easy to place front or rear.
• Occasional light squeak: The manual also notes that occasional squeak or squeal during light to moderate stops can be normal in some weather and driving conditions. A constant scrape is the warning; an occasional chirp on a damp morning usually is not.
• Steering wheel shake when braking: Points to front rotors with uneven thickness or pad deposits. A pulsation you feel in the pedal or seat but not the wheel often comes from the rear.
• Grinding metal-on-metal: The pad backing plate is touching the rotor. Replace the pads and plan on rotors on that axle.
• Weak parking brake: If the car rolls on a slope with the pedal set, the rear shoes may be worn or out of adjustment.
• VDC or brake warning lights: The manual warns that brake pads, rotors and calipers that are not recommended for the car, or that are badly worn, can keep VDC from working properly and turn on its warning light. A brake warning light with the parking brake off can also mean low fluid, which often follows pad wear.

For the 2016 model year, NHTSA's recall database lists no brake-system recalls for the Q50, so brake wear on these cars is normal service rather than a known defect.

To check pad life yourself, pull the wheels and look at the pad thickness on both the outer and inner pad at each corner. The inner pad often wears faster when caliper slides are dry, and you cannot see it without removing the wheel.

What to Replace, and What to Replace With It

Front brake job

Front pads are the most common brake service on a Q50. For a standard-package car, our 2014-2020 Infiniti Q50 and Q60 front ceramic brake pads are a direct replacement with low dust. Replace rotors at the same time if they are below the minimum thickness stamped on the rotor, scored, or causing a shake; you can browse replacement brake rotors and ceramic brake pads for the rest of the lineup. Always do both sides of an axle together.

Rear brake job

Rear pads and rotors are replaced the same way, with one extra step: the parking brake shoes live inside the rear rotor hat. Inspect the shoes whenever the rear rotors come off, and replace them if they are thin, contaminated with grease or fluid, or glazed. Infiniti's manual calls for a parking brake break-in whenever the parking brake shoes or the drums and rotors are replaced, or whenever parking brake holding power is weak. The procedure is in the factory service manual; skipping it leaves the parking brake with poor holding power until the shoes seat.

Parts worth replacing at the same time

• Hardware: New abutment clips and shims help prevent noise and uneven wear. See our brake hardware kits.
• Caliper slide pins: Clean and re-lubricate them with brake-specific grease. Replace any caliper that sticks, leaks or has torn boots; brake calipers are cheaper than a ruined set of pads and rotors.
• Brake fluid: Infiniti specifies Genuine Nissan Super Heavy Duty Brake Fluid or an equivalent DOT 3 fluid, replaced every 20,000 miles or 24 months under the standard schedule and every 10,000 miles or 12 months under severe conditions. A pad job is a good time to flush it if it is due.

If you want to do both axles at once, a front and rear pad and rotor kit is often the simplest order. Browse our full brake parts catalog or the Power Stop collection and filter for your Q50 year and brake package.

How Hard Is the Job?

Front pads and rotors on a standard-package Q50 are a moderate DIY job with basic hand tools, a torque wrench, a caliper piston tool and jack stands. Remove the caliper, hang it with wire so the hose is not stretched, swap the rotor and pads, and torque every fastener to the value in the factory service manual.

The rear is a step harder. You work around the parking brake shoes inside the rotor hat, the rotor may be rusted to the hub, and if the shoes have worn a lip into the drum area the rotor can hang on them. Back off the parking brake adjuster rather than hammering the rotor off. Then complete the parking brake break-in described in the service manual.

After any brake job, pump the pedal until it is firm before moving the car, check the fluid level, and bed in the new pads with a series of moderate stops. If the pedal feels low or soft, stop and find out why before driving.

Frequently Asked Questions

Do the front brakes on a Q50 wear faster than the rear?

Yes, in normal driving. Weight shifts forward when you brake, so the front brakes do most of the work, roughly 70 percent on a typical car. Expect to replace front pads first, but still inspect the rears at every pad service.

Should I replace all four brakes at once on my Q50?

Only if all four are worn. Brakes are always replaced in axle pairs, left and right together, but the front and rear axles can be done at different times. If the rear pads are close to the wear limit when you do the fronts, doing all four at once saves a second tear-down.

What is the scraping noise from my Q50's brakes?

It is most likely the audible wear indicator. Infiniti says the pads make a high-pitched scraping sound when they need replacing, first only when braking and later all the time. Have the brakes checked as soon as you hear it.

What brake fluid does the 2014-2020 Q50 use?

The owner's manual specifies Genuine Nissan Super Heavy Duty Brake Fluid or an equivalent DOT 3 fluid. Clean the reservoir cap before opening it and keep fluid off painted surfaces.

Do Q50 Sport brakes use the same pads as a base Q50?

Not always. Some Sport-trim cars have a larger performance brake package that takes different pads and rotors, while some Sport variants use the standard 2-piston front calipers. Check your calipers and match the part's fitment notes before ordering.

Does the Q50 have an electronic parking brake?

No. The 2014-2020 Q50 uses a foot-operated parking brake pedal with shoes inside the rear rotor hats, so rear rotor jobs include inspecting those shoes and performing the parking brake break-in afterward.

Sources

1. Infiniti: 2016 Q50 Owner's Manual and Maintenance Information - audible pad wear warning, DOT 3 fluid spec, foot parking brake, parking brake break-in, Brake Assist, VDC note, inspection intervals
2. Infiniti USA: 2018 Q50 Brake Fluid Maintenance Guide - brake fluid replacement every 20,000 miles or 24 months, 10,000 miles or 12 months severe
3. Motorist Assurance Program: Which Brakes Go Bad First - front brakes handle about 70 percent of braking force and usually wear first
4. Power Stop Z23 fitment data for 2014-2017 Infiniti Q50 - standard package rotor diameters and trim fitment, including 2017 Sport with 2-piston front calipers
5. NHTSA: 2016 Infiniti Q50 recalls - no brake-system recalls listed for this model year