2016-2022 Infiniti Q60 Rotor Replacement: Resurface or Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On an Infiniti Q60, resurfacing is only worth it when the rotor still has enough thickness left above its minimum after the cut and the problem is surface-level: judder from thickness variation, light glazing, or minor scoring. If the rotor is at or near the minimum thickness cast on it, has deep grooves from metal-to-metal contact, or has already been cut once, replace it. On the Sport and Red Sport 400 brakes in particular, fresh rotors are usually the better call because there is very little material to spare.

How the Q60 brake system is set up

The current Q60 coupe (chassis code CV37) arrived for the 2017 model year and runs four-wheel disc brakes with ABS. There are no rear drums on any trim. What changes between trims is the size and type of hardware, and that matters when you decide between machining and replacing:

The easiest way to tell which system you have is to look through the front wheel. A sport-brake car has a fixed caliper that wraps both sides of the rotor, often with the Akebono name on it. A standard car has a floating caliper on slide pins. If you are still unsure, the part number on the old rotor or a VIN lookup settles it.

Symptoms that point to a rotor problem

Infiniti's own brake service bulletin for all of its models (ITB00-024h) sorts brake complaints into noise, judder, and pedal feel, and it is a useful way to work out whether the rotors are actually the problem:

• Pulsing pedal or shaking steering wheel when braking. Infiniti calls this judder and says it is caused by rotor thickness variation and/or rotor runout. This is the classic reason to resurface or replace rotors.
• Groan while stopping. The bulletin links it to glazing of the rotor surface from heavy or frequent braking, and the fix it describes is new pads plus resurfaced rotors.
• Loud continuous squeal with or without braking. That is the pad wear indicator touching the rotor. It means the pads are worn out, not that the rotors are bad. Check the rotors anyway, because pads worn this far are often close to scoring them.
• Squeak on the first few cold stops in the morning, or a groan as you ease off the pedal at a stop. Infiniti lists both as normal. Neither one is a reason to touch the rotors.
• Grinding. The friction material is gone and the backing plate is cutting into the rotor. Plan on replacing rotors along with pads.

The bulletin also flags two causes owners rarely suspect. A car that sits for long periods rusts on the rotor area the pads do not cover, and that uneven surface can cause judder even after the rust wears off. Over-tightening lug nuts, especially with an air impact wrench, can also distort rotors and cause pulsation, so a Q60 that started shaking right after a tire service may only need its lug nuts set properly before anything else.

Resurface or replace: how to decide

Every rotor has three thickness numbers. Nominal thickness is what it measures when new. Machine-to thickness is the thinnest it can be cut and still go back on the car. Discard thickness is the point at which it must be replaced. According to MOTOR magazine's brake service guidance, a rotor below discard thickness should never be reinstalled, and rotors worn that thin are more prone to warping and other damage. On lighter late-model cars with thinner rotors, the first cut may be the only one the rotor can take.

To decide on a Q60:

1. Read the minimum thickness. It is usually cast into the rotor hat or edge. The factory service manual is the authoritative source. Do not rely on a figure from memory or another car.
2. Measure with a rotor micrometer at several points. MOTOR recommends checking thickness at eight points around the rotor, never just one. A rotor mic with one pointed anvil reads the true minimum of a scored rotor. The thinnest reading is the one that counts, and the spread between readings tells you how much thickness variation is there.
3. Do the math. If the cut needed to clean up the surface would take the rotor below machine-to thickness, replace it.
4. Look for damage a lathe cannot fix. Cracks, heat checking that runs deep, a lip so tall that the cut would remove too much, or a rotor that has already been machined once all mean replacement.

MOTOR also reports GM's long-standing rule that rotors should be turned only for specific problems such as deep scoring, excess runout, measurable thickness variation, or heavy corrosion, and not as a routine part of a pad change or to cure squeal. That logic applies to the Q60 as well: if the rotors measure well and run true, new pads alone are often all the car needs.

Why Sport and Red Sport 400 rotors are usually replaced

The sport brake rotors are large and expensive to make, but they do not carry much spare thickness. One aftermarket maker lists its replacement rear rotor for the 2017+ Q60 with Akebono sport brakes at 20 mm new and 18 mm minimum, which leaves only about 2 mm of total wear before it is scrap. Pads take some of that, a cleanup cut takes more, and a rotor that has been machined once has little life left. Combine that with the heat a 400-horsepower coupe puts into its brakes, and replacement is normally the better value on these cars. Check the minimum thickness on your own rotor; the figure above is one maker's spec, not Infiniti's.

On the standard brake system, a healthy rotor with mild thickness variation is a better candidate for a cut, as long as the measurement leaves it above machine-to thickness afterward.

If you resurface: do it the way Infiniti does

Infiniti's bulletin is specific. It names the ProCut PFM series on-car brake lathe as the approved tool for resurfacing and says judder should be corrected by turning the rotors on the car. An on-car lathe cuts the rotor true to the hub it actually spins on, which corrects runout that an off-car bench lathe can leave behind. The bulletin also warns to keep metal shavings off the ABS speed sensors and to stabilize the car so it does not rock during the cut.

If you cannot get the work done on an on-car lathe, new rotors are often the more reliable fix for pulsation on this car.

If you replace: what to do at the same time

• Replace pads with rotors. New pads bed properly into a fresh rotor surface; old pads carry the wear pattern of the old rotor. We carry front ceramic brake pads for the 2016-2022 Infiniti Q60, and you can browse more options in our ceramic brake pads collection.
• Replace in axle pairs. Do both front rotors or both rear rotors together so braking stays even side to side. Shop replacement brake rotors by your trim.
• Clean the hub face. Rust on the hub flange tilts the new rotor and creates runout. Infiniti's bulletin says to clean a rusty rotor-to-hub surface before installation.
• Index and check runout. The bulletin describes indexing a new rotor on the hub, checking runout with a dial indicator, and moving the rotor one stud at a time to find the position with the least runout.
• Refresh the hardware. Clips, shims, and slide pins on the standard calipers affect noise and wear. A brake hardware kit is cheap insurance.
• Torque the lug nuts correctly by hand with a torque wrench to the factory value, in a star pattern, rather than hammering them on with an impact gun.
• Bed in the brakes. Infiniti's burnishing procedure is a series of moderate stops from about 30 mph, each followed by about a minute of driving to cool the brakes, repeated ten times.

How hard is the job?

Replacing rotors on a Q60 is a moderate job for a home mechanic with a jack, stands, a torque wrench, and a rotor micrometer. On the standard brakes you remove the caliper and its bracket to free the rotor. On sport brakes the fixed caliper comes off as a unit. The rear rotors also house or work with the parking brake (the sport-brake rear rotors carry an iron sleeve for it), so release the parking brake and follow the service manual procedure for your trim when removing them. Resurfacing is different: doing it to Infiniti's standard requires an on-car lathe, which means a shop.

Frequently Asked Questions

Can I just put new pads on my Q60 without touching the rotors?

Yes, if the rotors measure above their minimum thickness, run true, and have no deep grooves. Routine pad replacement alone is not a reason to machine rotors. If you feel pulsation or see deep scoring, deal with the rotors at the same time.

Why does my Q60 shake when braking from highway speed?

Infiniti attributes judder to rotor thickness variation and runout. Common causes are uneven lug nut torque, rust from the car sitting, or rotors that have worn unevenly. Measure the rotors first; if they have room, an on-car cut can fix it, otherwise replace them.

Do Sport and base Q60 models use the same rotors?

No. Cars with the sport brake package use larger rotors with Akebono calipers, and those rotors will not fit the standard calipers, or the other way around. Check your calipers, the old rotor's part number, or your VIN before ordering.

Where do I find the minimum thickness for my rotors?

It is usually cast into the rotor itself, on the hat or the edge. The factory service manual lists it too. Use that number, not a general rule of thumb.

Should I replace front and rear rotors at the same time?

Not necessarily. Fronts usually wear faster. Replace rotors in pairs on the same axle, and only do the other axle if its rotors measure worn, scored, or out of spec.

Sources

1. Infiniti Technical Bulletin ITB00-024h, Brake Noise/Judder/Pedal Feel Diagnosis and Repair (NHTSA) - noise types, judder causes, on-car lathe, rotor indexing, burnishing procedure
2. MOTOR Magazine, On-Car and Off-Car Brake Rotor Service - nominal, machine-to and discard thickness; when to turn vs replace
3. Paragon rear rotor for 2017+ Infiniti Q60 (CV37) with Akebono sport brakes - 20 mm new and 18 mm minimum thickness; CV36 does not interchange
4. MOTOR Magazine, Effective Brake Service Techniques - measure thickness at eight points with a rotor micrometer; hub cleanliness and runout