2008-2013 Infiniti EX35 Brake Caliper Problems and Replacement

By Core Brake Parts Tech Team — Circleville, OH warehouse

Most brake caliper trouble on a 2008-2013 Infiniti EX35 is not a sudden failure. It is a slide pin that has lost its grease, a piston boot that has cracked with age, or a rubber hose that has started to hold pressure, and each one shows up as a pull, a drag, or one pad wearing far faster than its partner. Here is how the EX35 brake system is laid out, how to tell a bad caliper from a worn pad, and what to replace when you do the job.

How the EX35 Brake System Is Built

Infiniti's own specification sheet for the 2010 EX35 lists four-wheel power-assisted disc brakes on every version, rear-wheel drive and Intelligent All-Wheel Drive alike. There are no rear drums to adjust, so every corner has a caliper that can stick.

Two things follow from that layout. First, the thick vented front rotor and front caliper do most of the stopping, so the front calipers see the most heat and the most wear. Second, because EBD balances pressure front to rear automatically, a rear caliper that sticks can go unnoticed for a while; you often find it only when a rear pad is worn to the backing plate or a rear wheel is noticeably hotter than the others after a drive.

Symptoms of a Bad Caliper on the EX35

• Pull under braking. A caliper that is not applying fully lets the opposite side win. As a simple rule, if the vehicle pulls hard right when braking, inspect the left caliper first.
• Pull or drag when you are not braking. A caliper that does not release keeps its pad on the rotor. You may smell hot brakes, feel the vehicle coast less freely, or see more brake dust on one wheel.
• Uneven pad wear. An inner pad worn far thinner than the outer pad on the same wheel is the classic sign of a sticking slide pin. Normal wear is close to even.
• Noise. Pads that cannot move freely rattle, squeal, or wear out sooner than they should.
• Fluid at the wheel or a dropping reservoir. A wet caliper, a wet inside of the tire, or a soft pedal with a falling fluid level points to a leaking piston seal. This one is not optional; park it and fix it.
• Longer stops. When only one pad is really working on a corner, stopping distance grows.

What Actually Causes Caliper Problems

Slide pins that run out of grease

The EX35's floating calipers ride on slide pins sealed by rubber boots. ADVICS, a major OE brake supplier, lists the failure pattern plainly: the slide pin rusts once its grease is gone, and the boot and sleeve are damaged by heat and friction. Once the pin binds, the caliper stops centering and one pad does all the work. On a vehicle that is now well over a decade old and has seen winter roads, this is the most common caliper complaint by far.

Hardened piston seals and boots

Time and heat harden the rubber piston boot until it cracks. Water and grit get past it, the piston corrodes, and a rough piston then scrubs the bore seal every time you brake. The result is a piston that sticks out (drag) or a seal that starts to weep (leak).

Old fluid

Brake fluid absorbs moisture over time, and that moisture corrodes pistons and bores from the inside. Use the fluid type printed on the EX35's reservoir cap and follow the replacement schedule in the owner's manual.

Deteriorated flexible hoses

A rubber brake hose can deteriorate internally and act like a one-way valve, letting pressure in but holding it after you release the pedal. The symptom looks exactly like a stuck caliper. If a caliper drags and the wheel frees up the moment you crack the bleeder, suspect the hose as well as the caliper.

Diagnosing Before You Buy Parts

1. After a normal drive, carefully compare wheel temperatures by holding your hand near (not on) each wheel. One corner much hotter than its partner is dragging.
2. Lift the corner and spin the wheel. Some light pad contact is normal; a wheel that stops within a turn is not.
3. Pull the pads and compare inner and outer thickness. Big differences point to slide pins.
4. Remove the slide pins. They should slide by hand with light resistance. Rusted, pitted, or seized pins get replaced, not just greased.
5. Inspect the piston boot for cracks and the caliper body for wetness. Any leak means a caliper replacement.
6. Check the flexible hose for cracking, bulging, or the release symptom described above.

If the pins and boots are sound and the problem was only a dry pin, cleaning and lubricating may be all it needs. If the piston is sticking or leaking, replace the caliper.

The Fix: Which Parts to Replace

For a leaking or seized caliper, a remanufactured unit or a loaded caliper (one that comes with pads and hardware installed) is usually faster and more reliable than rebuilding the old one. Replace calipers in pairs on the same axle so both sides apply with equal force; a new caliper on one side and a tired one on the other can bring the pull right back. Browse replacement brake calipers and confirm fitment against your year and drivetrain.

What to do at the same time:

• Pads. A caliper that dragged has usually overheated or worn its pads unevenly. For the front axle we carry the EBC Redstuff ceramic low-dust front pads for the EX35 and the EBC Greenstuff front pads. For the rear, see the EBC Redstuff ceramic rear pads or, for 2010-2013 models, the Hawk HPS 5.0 rear pads.
• Rotors. Drag heats the rotor on that corner. Measure thickness and runout against the minimums in the service manual; if the rotor is scored, heat-spotted, or below spec, replace it. Options include the EBC GD Sport slotted front rotors and the EBC USR slotted rear rotors, or browse all brake rotors.
• Hardware. New slide pins, boots, and pad clips from a brake hardware kit cost little and prevent a repeat.
• Hoses. On a vehicle this age, original rubber hoses deserve a close look. Replace any that are cracked or suspect with new brake hoses, ideally in pairs.
• Fluid. Opening the system is the right time to flush it with fresh fluid of the type on the cap.

How Hard Is the Job?

Replacing an EX35 caliper is a moderate job for a home mechanic with a jack, stands, a torque wrench, a flare-nut wrench, and a helper or bleeder kit. The basic steps: disconnect the brake hose at the caliper, remove the caliper bolts, swap the caliper, install new sealing washers where used, reinstall with fresh pads and lubricated pins, then bleed. Torque the caliper and bracket bolts to the values in the factory service manual; do not guess them, since loose caliper mounting bolts are a known way for a caliper to rotate or separate from its bracket.

Bleeding is the part that needs care. The EX35 has 4-channel ABS, so do not let the master cylinder reservoir run dry during the job; air that reaches the ABS unit is harder to purge. Bleed in the order the service manual specifies, and pump the pedal to seat the pistons before you move the vehicle. Bed in new pads with a series of moderate stops before any hard braking.

A quick recall note: NHTSA's recall database for 2008 through 2013 EX35 models shows no brake-related safety recalls; the listed campaigns cover air bags, the steering column, and equipment. Caliper work on this vehicle is ordinary wear-and-age maintenance. It is still worth running your VIN through a recall lookup for any open campaigns before other service.

Frequently Asked Questions

Do I have to replace EX35 calipers in pairs?

It is strongly recommended. Replacing both calipers on the same axle keeps clamping force equal side to side, which prevents a pull. The opposite caliper is the same age and has seen the same heat and corrosion.

Can I just grease the slide pins instead of buying a caliper?

Yes, if the pins are only dry. Clean the pins and bores, replace any torn boots, and use a brake-specific lubricant rather than general petroleum grease, which can swell rubber parts. If the piston itself sticks or the caliper leaks, greasing will not fix it.

Why is only one of my EX35's inner pads worn out?

That is the signature of a binding slide pin on that caliper. The piston pushes the inner pad, but the caliper cannot slide to pull the outer pad in, so the inner pad does all the work.

Are the front and rear calipers different on the EX35?

Yes. The front uses a larger 12.6-inch vented rotor and the rear a 12.1-inch disc, so the calipers, pads, and rotors are different parts front and rear. Order by axle and confirm your model year and drivetrain.

Is it safe to keep driving with a sticking caliper?

No. A dragging brake overheats the pad and rotor on that corner, which can cook the fluid and cut braking performance, and a caliper that is not applying lengthens your stops. Fix it promptly.

Do I need to bleed the whole system after a caliper swap?

At minimum, bleed the corner you opened until clean fluid with no bubbles comes out. If the fluid is old or the reservoir ran low, flush the whole system.

Sources

1. 2010 Infiniti EX35 Technical Specifications (Infiniti spec sheet) - rotor sizes, 4-wheel disc, ABS/EBD/BA, RWD and AWD, wheel sizes
2. NHTSA recall database, 2008 Infiniti EX35 - listed campaigns are non-brake
3. NHTSA recall database, 2010 Infiniti EX35 - no brake recall listed
4. ADVICS: Troubleshooting caliper slide pin sticking - causes and fix for sticking slide pins
5. Brake and Front End: Brake Caliper Service - caliper symptoms, seal and boot failure, replace vs rebuild