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How To Change Brake Pads

























How to Change Brake Pads

Better brakes may not mean better gas mileage. However, better brakes improve safety. This is an overview of brake pads, changing brake pads, brake rotors, and brake fluid. Or learn about Big Brake Kits.


EBC Brake Pads

Getting performance brake pads are a great way to improve safety and fun. Brake pads are easy to install. A set of performance brake pads cost about $10 more than the common brake pads. It's a cheap upgrade that provides immediate gratification. The brands I would recommend are EBC, Bendex and Power Stop. If there's a Wilwood brake pad available for your car, by all means get that! It's the author's opinion that Willwood makes the best brakes.

EBC is an English company that manufactures performance brake pads. Like most brake pad manufacturers they offer several different levels of braking performance. Each level has its own set of compromises. A low-priced brake pad is usually a noisy semi-metallic brake pad that leaves dark brake dust on wheels. A performance brake pad is usually ceramic, quiet, produces little brake dust, and costs about $10 more. A race-ready brake pad will usually be noisy, dirty, and very effective.

The EBC Redstuff is the performance ceramic brake pad. The performance brake pads usually offer the best of all compromises. The test car was fitted with EBC Redstuff brake pads on the rear wheels.

Photo of the brake pad installation:


How to Change Brake Pads

You'll need:
• a jack
• 16 inch tongue and grove pliers
• open end or socket wrench set (make sure you have a metric set)
• lug nut wrench, preferably a breaker bar
• long flathead screwdriver
• new brake pads

Prepare to get dirty ;-)

If you have a hubcap, pull it off. Loosen the lug nuts first. This could be the most painful part of the process if a shop previously used an impact wrench to tighten the lug nuts. This is why a breaker bar is recommended. A breaker bar is a long non-ratchet bar with a 0.5 inch socket attachment at the end. If necessary, use a hollow pipe placed over the handle of the breaker bar to gain more leverage. Once all lug nuts have been loosened a half turn, place the jack under a jack-point recommended in the car's user manual. Using a specified jack point will prevent the chassis from being damaged. Any ole place won't do. Choose wisely!

Jack up the corner of the car until the tire no longer contacts the ground. A quarter inch of space between the tire and the pavement is sufficient. Remove the lug nuts and wheel. Find the two caliper bolts. Be careful to find the bolts and do not to loosen the bleeder valve (it looks like a bolt too). The two bolts hold the caliper to the knuckle. Use an open end wrench or socket wrench to remove the two caliper bolts.

Pull the caliper out. It will pull out perpendicular to the axle. Use the long flathead screwdriver to pry it out if necessary. Use the 16 inch tongue and groove pliers to compress the piston all the way into the bore. Put one jaw right in the middle of the inside brake pad and the other jaw on a flat spot on the back of the caliper and squeeze. The piston will sink into the bore. On a floating caliper, the outside brake pad is clipped on and the inside pad usually snaps into the piston. Use your fingers to remove the brake pads. Do NOT damage the piston seal with a screwdriver in an effort to pry them out.

Press the new brake pads in with your fingers. Do not damage the brake pads. With the new brake pads in place, slip the caliper over the rotor. The steel sleeves that allow the caliper to float may need to be pulled back to allow the caliper to fully seat. Reinstall the two caliper bolts. Be careful NOT to cross thread the bolts. The bolts should go in by turning the bolt by hand. Then tighten with an open end or socket wrench. Tighten the bolts firmly. Do not go crazy trying to get it super tight. Over-tightening can damage costly parts.

Reinstall the wheel and tighten the lug nuts with a wrench till they are just hand tight and hold the wheel firmly to the hub (the wheel doesn't wiggle). Lower the car and remove the jack. Tighten the lug nuts in a crossing pattern. NEVER tighten one bolt all the way and then the next bolt! Tighten each lug nut a little at a time. Tighten one lug nut a little bit and then tighten the lug nut opposite of that one a little bit, and then another lug nut opposite of that one until each lug nut is tightened the same amount. Continue this sequence until all lug nuts are tight to 75 - 100 ft lbs. That's a lot of force! Never use an impact wrench to tighten lug nuts (or anything else on a car!).

Follow the break-in procedure outlined by the brake pad manufacturer. This usually involves some regular light braking.


Brake Rotors

There is a lot of hype about performance rotors. There are slotted rotors, cross-drilled rotors, coated rotors, cryogenically treated rotors, and slotted rotors that are cross-drilled and cryo-treated. These custom rotors can cost $50 - $500+ per rotor. I have never seen any believable data that supports an improvement in braking distance due to these custom rotors. I have seen evidence that cross-drills and slots are the source of thermal cracks at the outer edge of the rotor.

Custom rotors are all marketing hype. There is no benefit in to using these. They might look pretty, but that's it. Coatings used on the surface of the rotor are quickly rubbed off by the brake pads. Thermal cracks mean the rotor needs to be replaced. Cryo-treating rotors is just silly. It does nothing whatsoever.

The best rotors to use are the plain old cast iron rotors. The uniform surface is more difficult to crack. And the plain old smooth faced rotors cost less and provide the same braking performance as the more expensive custom rotors.

Never get a rotor resurfaced or 'turned.' This makes the rotor thinner. A thinner rotor is not able to cope with the heat and warps (I've seen this many times). All the kinetic energy of a moving car is turned into heat that the rotor absorbs. Thicker rotors can absorb more heat without deforming. A deformed rotor makes a car dangerous. The vehicle and steering wheel shakes under braking. And it gets worse over time. The vibrations lengthen braking distance and reduce the control a driver has over the car. It can also adversely affect the anti-lock braking system.

Fitting a super thick rotor in a stock car is not really an option. It just won't fit between new brake pads. If a mechanic tells you that the rotors need to be 'turned' tell him to replace the rotors.


Brake Fluid

This is something that's often horribly neglected. Brake fluid does not compress. This quality is very important for brakes. Stepping on the brake pedal pushes fluid from the brake's master cylinder to the calipers that squeeze the rotors. If the brake fluid is compressed, stepping on the brake pedal will not stop the car.

But brake fluid can compress! It can compress if it absorbs water. Unfortunately brake fluid is very good at absorbing water. Water reduces the boiling point of brake fluid. If the brake fluid boils because the brakes are hot (and they do get very hot), the gas bubbles can be compressed. This means that stepping on the brake pedal won't stop the car.

Use the brake fluid recommended by the car's manufacturer. And change it every time the brake pads are replaced. I prefer DOT 5 or better brake fluid because of the higher boiling point and it won't destroy paint or plastic. However DOT 4 should work well for the average commuter.

For the Do-it-yourselfers out there, I highly recommend Speedbleeders. These are one way check valves that replace the conventional bleeders. This enables one person to bleed the brakes and prevent air from getting into the brake fluid. These can be purchased online at Speedbleeder.com or at CarQuest, O'Reilly's and similar auto parts stores.


Learn about the big brake kit installed on the test car.


Let's Review

Performance brake pads are great!

I recommend EBC, Bendex, Wilwood, and Power Stop

The simple smooth faced rotors are the best value.

Change the brake fluid every time the brake pads are replaced.


Step3: Improved Maintenance
Engine Oil
Oil Filters
Engine Coolant
Ceramic Additive
Air Filters
Spark Plugs
Tire Selection
Wiper Arm Adjustment


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