2007-2011 Acura CSX Front vs Rear Brakes: What Wears First and What to Replace

By Core Brake Parts Tech Team — Circleville, OH warehouse

On a 2007-2011 Acura CSX the front pads usually wear out first, because the front axle carries the engine and takes most of the load in a stop. But this car has rear disc brakes and electronic brake force distribution, so the rears work harder than on an older car, and rear pads that are close behind the fronts are normal, not a sign of trouble. Measure both ends before you buy, and replace pads in axle sets.

How the CSX brake system is laid out

The CSX was the Canadian-market Acura built on the eighth-generation Civic sedan platform. Published spec sheets for both the base CSX and the Type-S list disc brakes at both the front and the rear, with anti-lock brakes. Auto123's specs for the CSX also list electronic brake force distribution (EBD), and the Civic Si sedan, which shares the Type-S drivetrain, carries the same four-wheel disc, ABS and EBD layout on the same 215/45R17 tire size.

That matters for this topic. Many compact sedans of this era put drum brakes on the rear axle of their cheaper trims, and those drums can go a very long time between services. The CSX does not do that. Every trim has a rear caliper, rear pads and rear rotors, so the rear axle is a real maintenance item.

The front brakes use a larger, vented rotor to handle more heat; the rear uses a smaller rotor. Front pad listings are often split between the base car and the Type-S, so confirm your trim before ordering pads.

Which end wears first, and why

When you brake, weight shifts forward. The front tires gain grip and the rear tires lose some, so the front brakes can do more of the stopping without locking up. On older cars without electronic control, the front brakes did the large majority of the work and front pads commonly wore out about twice as fast as the rears.

EBD changes that balance. The Traffic Injury Research Foundation describes EBD as making the brake force at each wheel proportional to that wheel's load at the moment. In practice the system lets the rear brakes do as much as the rear tires can take without locking, then trims rear pressure when the rear gets light. The result on cars like the CSX is that rear pads carry a bigger share than they used to, and it is common to find the two ends wearing at similar rates.

What that means for a CSX owner:

• Typical pattern: fronts go first, with the rears not far behind. Plan on checking the rears every time the fronts are done.
• Hard, late braking and a lot of city driving push more work to the rear, because EBD keeps the rear tires engaged in firm stops.
• Rears worn well past the fronts is the pattern to question. That usually points to a rear caliper that is not releasing fully, not to EBD.

Symptoms and how to check each end

Use these to tell which end needs attention:

• High-pitched squeal while driving that stops when you brake: the pad wear indicator tab is touching the rotor. Find which wheel it comes from before ordering.
• Grinding: the friction material is gone and the backing plate is on the rotor. Stop driving on it; the rotor on that corner needs replacing, not just the pads.
• Pedal pulsation or steering-wheel shake under braking: usually front rotor thickness variation. A shake felt more in the seat than the wheel often points to the rear rotors.
• Car pulls to one side: a sticking front caliper or a collapsed hose on that side.
• One rear wheel hot after a drive, or a rear pad worn to a taper: a sticking rear caliper slide pin or a parking brake mechanism that is not fully releasing.

To inspect, look through the wheel spokes at the outer pad on each corner, then pull the wheel to see the inner pad, which often wears faster. Measure the remaining friction material against the minimum in the service manual. Check the rotor face for deep grooves, a raised lip at the outer edge, or blue heat marks.

What to replace, and what to replace with it

Always replace pads as an axle set, both sides of the front or both sides of the rear, so the car brakes evenly. Whether to replace the rotors depends on what you find:

• Replace rotors if they are below the minimum thickness stamped on the rotor or listed in the service manual, if there is a lip you can catch a fingernail on, if the pedal pulses, or if the pads were run to metal.
• Replace the hardware: new abutment clips and shims help the new pads slide freely and stay quiet. A brake hardware kit is inexpensive insurance.
• Service the slide pins: clean them and re-grease with a brake-specific lubricant. A dry pin causes the uneven pad wear described above.
• Check the rubber hoses at each corner for cracks or bulging while you are there.
• Brake fluid: use the fluid type printed on the master cylinder reservoir cap and in the owner's manual, and replace it on the interval in the maintenance schedule. Old fluid absorbs moisture and can make the pedal feel soft after hard use.

For street driving, a good ceramic pad is quiet, low-dust and easy on rotors; see our ceramic brake pads and replacement brake rotors. Type-S owners who drive hard or do track days can step up to a performance compound such as the EBC Bluestuff NDX front pads for the 2007-2011 CSX Type-S, a high-friction sport and race material. A pad like that trades some noise and dust for heat capacity, so it suits an enthusiast more than a daily commuter.

How hard is the job?

The front brakes are a straightforward driveway job for someone with basic tools, a jack and stands, and a torque wrench. Remove the caliper bolts, swing or remove the caliper, swap pads and clips, and replace the rotor if needed. Torque the caliper and bracket bolts to the values in the factory service manual and the wheel nuts to the owner's manual figure.

The rear takes a bit more care because the rear caliper also works the parking brake. Make sure the parking brake is released before you start. If the rear piston will not push straight back into the caliper, do not force it with a clamp; it is a screw-in type and must be turned back in with a caliper wind-back tool. Line the piston slot up with the tab on the back of the new pad. After either axle, pump the pedal until it is firm before moving the car, then bed in the new pads with a series of moderate stops from medium speed.

Frequently Asked Questions

Does every Acura CSX have rear disc brakes?

Yes. Spec sheets for both the base CSX and the Type-S list disc brakes front and rear with ABS, so every trim has rear calipers, pads and rotors to maintain.

Why are my CSX rear pads almost as worn as the fronts?

The CSX has electronic brake force distribution, which lets the rear brakes take as much load as the rear tires can handle. That makes near-even wear normal. Rear pads that are far more worn than the fronts, or worn unevenly, point to a sticking rear caliper instead.

Should I replace all four corners at once?

Only if both axles need it. Replace pads in axle pairs and measure each end separately. On this car many owners do find both ends close to the limit at the same visit.

Do I need new rotors with new pads?

Not always. If the rotors are above minimum thickness, have no lip or deep grooves and the pedal does not pulse, they can stay. If the pads ran to metal, replace the rotors.

Are Type-S front pads the same as the base CSX?

Not necessarily. The Type-S shares its drivetrain with the Civic Si, and front pad listings are often split by trim. Check the fitment notes for your exact trim before ordering.

Sources

1. The Car Guide: 2009 CSX Type-S spec sheet - front and rear disc brakes with ABS, 197 hp 2.0L, 215/45R17 tires
2. The Car Guide: 2009 CSX base spec sheet - base CSX also uses front and rear disc brakes with ABS, 155 hp 2.0L
3. Auto123: 2009 Acura CSX technical specs - 4-wheel disc brakes, anti-lock brakes and electronic brake force distribution
4. Auto123: 2008 Honda Civic Si sedan technical specs - the Civic Si sibling also uses 4-wheel discs, ABS and EBD on 215/45R17 tires
5. Brain on Board (Traffic Injury Research Foundation): Electronic brake-force distribution - how EBD sets brake force at each wheel in proportion to its load
6. Rick's Free Auto Repair Advice: What is electronic brake force distribution - older cars put most braking on the front; with EBD front and rear wear can be close to even