2009-2012 Infiniti G37 Front vs Rear Brakes: What Wears First and What to Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2009-2012 Infiniti G37, the front brakes almost always wear out first, usually by a wide margin, because the front axle does most of the stopping as weight shifts forward. The rear pads still wear, and the rear rotors can glaze, rust or run low on thickness, so check all four corners at every front brake job. What you replace depends heavily on whether your car has the standard brakes or the larger Sport Brakes.

Which Brakes Does Your G37 Have?

Every G37 in these years uses power-assisted vented disc brakes at all four wheels, with a 4-channel, 4-sensor ABS, Electronic Brake force Distribution (EBD) and Brake Assist, according to Infiniti's own press kits. The difference that matters for parts is the Sport Brake package.

Infiniti states that the upgraded brakes were not available on the G37x AWD, so an AWD car is a standard-brake car. The Sport calipers are aluminum and carry INFINITI lettering, which makes them easy to spot through the wheel spokes. If you bought the car used and are not sure, look at the front caliper: a large caliper with INFINITI lettering and pistons on both sides of the rotor is the Sport setup. Pads and rotors are not interchangeable between the two systems, so identify the system before you order anything.

Why the Fronts Wear First

When you brake, weight transfers to the front of the car. The nose dips, the front tires gain grip, and the front brakes take on most of the work. Power Stop's rotor guide puts it simply: front axles carry more weight, so front rotors and pads wear more quickly than the rears. On a Sport Brake G37 the hardware reflects this: a 4-piston caliper and a 14.0-inch rotor up front against a 2-piston caliper and a 13.8-inch rotor at the rear.

EBD changes the picture slightly. Instead of a fixed mechanical proportioning valve, EBD uses the ABS hydraulic unit to vary front-to-rear brake pressure based on load and conditions. Brake & Front End notes that some manufacturers tune EBD to use the rear brakes more under light braking to reduce nosedive, which can make rear pads wear faster than owners expect. On a G37 the rears normally outlast the fronts, but do not assume they are fine just because the fronts are the ones making noise.

Driving style widens the gap. The G37 carries a 328-horsepower 3.7-liter V6, and hard stops from speed load the fronts far more than gentle commuting does. Owners who drive aggressively often go through front pads well before the rears need attention.

Symptoms: Front Problem or Rear Problem?

• High-pitched squeal on light braking: usually a pad wear indicator, most often on the front. Pull the wheels and look at pad thickness on both axles.
• Steering wheel shake when braking: points to the front rotors. Uneven thickness or pad deposits on the front discs transmit straight into the steering.
• Pedal pulsation without steering shake: can be the rear rotors. You feel it through the seat and pedal rather than the wheel.
• Grinding or scraping: metal-to-metal contact. Stop driving on it; a worn-through pad will score the rotor and can damage the caliper.
• Car pulls to one side under braking: a sticking caliper slide or piston on one side, or contaminated pads.
• Parking brake weak or lever travels far: the rear parking brake shoes inside the rear rotor hat need adjustment or replacement. This is separate from the rear pads.

Power Stop also lists visible scoring or grooves, blue heat discoloration and longer stopping distances as signs rotors need attention. Check rotor thickness with a micrometer at the thinnest point in the pad contact area and compare it to the minimum thickness marked on the rotor itself, which can be on the hat, the edge or inside the vanes.

What to Replace, Axle by Axle

Front brake job

Most G37 front jobs mean new front brake pads and, often, new front brake rotors. Resurfacing a rotor that is already close to its minimum thickness just shortens its life, so measure before you decide. Replace pads and rotors in axle pairs, never one side.

For Sport Brake cars, a performance street pad is a popular choice. The Hawk HPS front brake pad set for the 2009-2012 G37 Sport uses Hawk's High Performance Street compound, which Hawk describes as having higher friction than stock pads, better fade resistance and less dust. Confirm your caliper type against the listing's fitment before ordering.

Rear brake job

Rear pads typically last well past the first front change. When you do the rears, measure the rear rotors against their stamped minimum, since rust ridges and glazing on the rear discs are common on cars that see little hard braking. While the rotors are off, inspect the parking brake shoes and adjust them; worn or seized shoes are a common reason a parking brake will not hold on a hill.

Replace at the same time

• New pad hardware (abutment clips and shims) from our brake hardware kits. Reusing tired clips causes noise and uneven wear.
• Clean and lubricate the caliper slide pins on standard calipers. The Sport calipers are fixed multi-piston units, so check that each piston moves freely and the dust boots are intact.
• Brake fluid, if it is dark or has not been changed in years. Use the fluid type printed on the reservoir cap and in the owner's manual.
• If a caliper is leaking or a piston is seized, see our brake calipers and replace them in axle pairs.

How Hard Is the Job?

A front pad and rotor job on a G37 is a reasonable driveway project for someone with a floor jack, jack stands, a torque wrench and basic hand tools. The Sport calipers are large; support them so they never hang from the brake hose. Pistons on fixed calipers should be pushed back evenly with a pad spreader so they do not cock in their bores. Torque caliper bolts and lug nuts to the values in the factory service manual, and tighten lugs in a star pattern.

Rear jobs take a little longer because the parking brake shoes sit inside the rotor hat. If the rotor will not come off, back off the parking brake adjuster instead of hammering on the rotor. After any job, pump the pedal until it is firm before the car moves, then bed in the new pads with a series of moderate stops before any hard driving.

If you are not sure which system your car has, browse our full brake parts catalog by vehicle and check the fitment notes on each listing.

Frequently Asked Questions

How much faster do G37 front brakes wear than the rears?

There is no single ratio, because it depends on driving style and how EBD apportions pressure, but on most G37s the front pads are replaced noticeably more often than the rears. Inspect both axles at every front job rather than assuming the rears are good.

Can I put Sport brake pads on a non-Sport G37?

No. The Sport Brake calipers use different pads and larger rotors than the standard system. Converting requires calipers, rotors, mounting hardware and pads as a matched set, and your wheels must clear the larger calipers.

Does the G37x AWD have the Sport brakes?

Infiniti's press materials state the upgraded brakes were not available on the G37x AWD, so AWD cars use the standard brake system. Order parts for the standard brakes.

Should I replace rotors every time I replace pads?

Not automatically. Measure them. If they are above minimum thickness, free of deep grooves and not causing vibration, they can stay. If they are near the limit or cause pulsation, replacing them with the pads is the better call.

Why does my G37 parking brake feel weak after a rear brake job?

The parking brake uses separate shoes inside the rear rotor hat. If they were backed off to remove the rotor and not readjusted, or if the shoes are worn, the lever will travel far and hold poorly. Adjust or replace the shoes.

Sources

1. INFINITI - 2010 G Sedan Press Kit - 4-wheel vented discs, ABS/EBD/Brake Assist, Sport Brakes 14.0-inch front and 13.8-inch rear with 4-piston/2-piston calipers, not available on G37x AWD, 328-hp 3.7-liter V6
2. INFINITI - 2010 G37 Coupe Press Kit - Coupe Sport 6MT and Journey Sport Package aluminum calipers with INFINITI lettering and rotor sizes
3. Power Stop - How to Tell If You Need New Brake Rotors - front axle weight and faster front wear, minimum thickness location and measurement, rotor warning signs
4. Brake & Front End - Electronic Proportioning Valve - how EBD varies front and rear pressure and can increase rear pad wear
5. Hawk Performance - HPS - HPS compound friction, fade resistance and dust characteristics