2016-2022 Infiniti Q60 Brake Rotor Minimum Thickness and When to Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2016-2022 Infiniti Q60, a brake rotor has to be replaced once any measured point falls below the minimum thickness stamped on the rotor itself, usually shown as "MIN TH" followed by a value in millimeters. For the 320 mm front rotor listed for the 2.0t coupe, the replacement catalog value is 28 mm new with a 26 mm minimum; the large 350 mm x 20 mm rear rotor has an 18 mm minimum. Because the Q60 came with more than one brake package, confirm your rotor size before you trust any number, including these.

Which brakes does your Q60 have?

The second-generation Q60 coupe uses ventilated disc brakes at all four corners. There are no rear drums and no solid rear rotors on these cars, so both axles have a vented rotor with cooling vanes between two friction faces. What changes between trims is the size of those rotors and the calipers that clamp them.

Broadly, the Q60 lineup splits into three brake setups:

• 2.0t four-cylinder cars: a 320 mm front rotor that is 28 mm thick when new.
• 3.0t V6 cars: base and Premium trims use standard-size brakes, while cars equipped with the sport brake package get larger rotors and multi-piston calipers.
• Red Sport 400: the largest brakes in the range, with big multi-piston calipers and noticeably larger rotors front and rear.

The quickest way to tell what you have is to look through the wheel spokes. The sport brake package has noticeably larger multi-piston calipers that fill most of the wheel, and the rotor nearly reaches the inside of the rim. If you are not sure, measure the rotor's outside diameter across the center of the hub. A reading close to 12.6 inches is the 320 mm front; a clearly larger reading means a sport brake rotor. Order parts by that measurement, not by model year alone.

Minimum thickness specs for Q60 rotors

The table below lists the dimensions published in Brembo's replacement rotor catalog for discs listed against the Q60 coupe built from September 2016 on. These are the dimensions of a new replacement rotor and the wear limit printed for that rotor.

Two cautions. First, these applications come from a European catalog, and North American Q60 trims do not always share the same rotors; some cars use a different rear rotor, and sport brake cars use larger rotors at both ends. Second, every rotor maker stamps its own minimum on its own part. If an aftermarket rotor is on the car now, the value stamped on that rotor is the one that governs it. In each listed case the margin between new and minimum is only 2 mm, which is why rotors on a heavy, powerful coupe can reach the limit within one or two pad sets.

How to measure a Q60 rotor correctly

You need a micrometer or a vernier caliper with jaws long enough to reach past the wear lip. A ruler is not accurate enough when the whole wear allowance is 2 mm.

1. Safely lift and support the car on stands, then remove the wheel.
2. Find the "MIN TH" marking. It is usually on the rotor hat or the outer edge. Write it down.
3. Measure the friction surface just inside the raised lip that forms where the pad stops. Measuring on the lip gives a falsely thick reading.
4. Take readings at at least four points around the rotor, turning it between each one. Brembo's guidance is to use the lowest reading as the thickness of the whole rotor.
5. Compare that lowest reading with the stamped minimum. If it is below the minimum, the rotor is done.

While you are there, look for heat cracks running from the vents or the edge, scoring deep enough to catch a fingernail, and blue or dark heat spots. Any of those is a reason to replace the rotor even if it still measures above minimum.

Symptoms that your Q60 rotors are near the limit

Thin rotors hold less heat and are structurally weaker. Brembo lists the consequences of running a rotor below its minimum as thermal cracking, vibration and noise, longer pedal travel, and fade under sustained hard use such as long downhill grades. On a Q60, owners usually notice it this way:

• Steering wheel shake or pedal pulsation when braking from highway speed. Thin rotors distort more easily when hot.
• A deep wear lip on the outer edge that you can see through the wheel.
• Fade after spirited driving. A rotor with less iron reaches high temperatures faster, and the pedal starts to feel soft or long.
• Grinding or a metallic scrape. This usually means the pads are gone and the backing plate has started cutting the rotor, which almost always ends the rotor's life.
• A pad wear squeal or warning. Pads and rotors wear together, so every pad change is the right time to measure.

Replace or resurface?

Machining (turning) a rotor removes metal from both faces. With only 2 mm between a new 28 mm front rotor and its 26 mm minimum, there is rarely enough left to machine a used Q60 rotor and still finish above minimum, particularly after it has been through a full set of pads. Most shops will measure, and if the rotor would end up at or under the limit after cleanup, it gets replaced instead.

Brembo's rule of thumb is to replace rotors at every second pad change and to always replace them in axle pairs, even if only one side has worn past the minimum. Mixing a new rotor with a worn one on the same axle can make the car pull under braking.

What to replace with the rotors

When the rotors go, fit new pads on the same axle. Bedding fresh pads onto fresh rotors builds an even transfer layer and avoids the noise and vibration that come from putting new pads on a grooved surface. For a daily-driven 2.0t or 3.0t coupe, ceramic brake pads are a sensible choice for low dust and quiet operation; we carry 2016-2022 Infiniti Q60 front ceramic brake pads for this car. Measure first, then pick replacement brake rotors in the diameter that matches yours.

Also worth doing at the same time:

• New brake hardware (abutment clips and shims) so the new pads slide freely.
• Clean and lubricate the caliper slide pins with brake-specific grease.
• Check brake fluid condition and level, and inspect the flexible brake hoses for cracks or bulging.
• Clean rust off the hub face before fitting the new rotor so it sits flat; rust trapped between hub and rotor causes runout and pulsation within a few thousand miles.

Torque the caliper bracket bolts and lug nuts to the values in the factory service manual, using a torque wrench and a star pattern on the lugs. On the standard brakes this is a straightforward driveway job for a careful DIYer. On sport brake cars with fixed multi-piston calipers the procedure differs and the parts are larger, so measure twice before ordering.

Frequently Asked Questions

What is the minimum rotor thickness on a 2017 Infiniti Q60?

It depends on the brake package. The 320 mm front rotor listed for the 2.0t is 28 mm new with a 26 mm minimum in Brembo's catalog, and the 350 mm rear rotor is 20 mm new with an 18 mm minimum. Always confirm against the MIN TH value stamped on the rotor that is actually on your car.

Where is the minimum thickness marked on the rotor?

Look for "MIN TH" followed by a number in millimeters, usually cast or stamped on the rotor hat or around the outer edge. If it has rusted over, clean the area with a wire brush.

Can I replace just the pads and keep my Q60 rotors?

Yes, if every measurement is above minimum and the surface is smooth with no cracks or heavy grooves. Many owners get two pad sets out of one set of rotors, which matches the common guidance of replacing rotors at every other pad change.

Do the Red Sport 400 brakes use the same rotors as the base Q60?

No. The Red Sport 400 uses larger rotors and multi-piston calipers than the standard brakes, so standard-size parts will not fit those cars. Measure the rotor diameter and read the MIN TH stamp on the rotor that is on the car.

Should I replace both rotors on an axle if only one is worn?

Yes. Rotors should be replaced in pairs on the same axle so braking force stays balanced side to side.

Sources

1. Brembo - Minimum brake rotor thickness - MIN TH marking, measure at four or more points, use the lowest reading, replace in pairs, effects of thin rotors, replace rotors every other pad change
2. Brembo catalog - disc 09.E235.11 - 320 mm front ventilated disc, 28 mm thickness, 26 mm minimum
3. Winparts - Brembo 09.E235.11 applications - front disc listed for Q60 Coupe 2.0 T from 09.2016
4. Winparts - Brembo 09.E528.11 applications - 350 mm rear disc, 20 mm thickness, 18 mm minimum, listed for Q60 Coupe 2.0 T and 3.0 T AWD
5. CarExpert - 2017 Infiniti Q60 specs - four disc brakes, all four ventilated