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The following procedure is pretty common to many vehicles and so applies to more than a 1994 Toyota Corolla.

If this is the second time the brake pads have been replaced, it is likely you will need new rotors as they will be worn too thin to have turned and reused.

If you buy the rotors at the same times as the pads, you will save a trip to the part store with your car up on jack stands. You can always return the unused rotors if you don't need them.

Assume the vehicle has the parking brake set, rear wheels are chocked, the entire front is jacked up, supported with jack stands and the front wheels are removed. On the back of the caliper is a small nut like protuberance. It may have a rubber cap. Remove the cap. This is the caliper bleed valve screw. Put one end of a piece of 1/8 inch vinyl hose over the bleed valve and the other end in a container. It is usually an 8 mm size. On some cars, it may be a 10 mm. Open the bleed valve with a open end or box wrench. If you are using a box wrench, put it over the bleed screw before you put the vinyl hose on. An adjustable wrench is a good way to round of the corners of a tight bleed valve screw. Avoid adjustable wrenches if you can. .

Use a heavy screwdriver or tirelever to push the piston in by pushing the lever in between the disk and pad. This will give leverage to wedge the disk pads back. Do not put any pressure on the rubber caliper boot/seal around the piston as you could poke a hole in it and then you would have to replace the entire caliper! The pads can be damaged but they will not be used again. Do this slowly so the fluid does not squirt all over. You will only get brake fluid in your eyes once in a lifetime. Avoid the first time at all costs. Continue to push the piston back into the cylinder until it is retracted as far as possible. You will likely need to do it in a 2 step process as describe below, otherwise you will not be able to get caliper back over new pads. Tighten the bleed valve. Clean up any spills.

Remove the two 17 mm bolts. The caliper should slide off. Do not let the caliper hang as it can damage the flexible brake line. Remove and replace the inboard pad and reinstall the caliper. Loosen the bleed valve again and squeeze the piston in the rest of the way by leveraging against the rotor, not the new brake pad. Tighten the bleed screw. Remove the caliper again and remove and replace the outboard pad. If the rotor is in good shape, you can now reinstall the caliper. Install and tighten the two bolts.

On a Honda Civic, the procedure is the same except, behind the caliper there are 2 size 14mm bolts and 2 size 17 mm bolts. Undo the bottom 14 mm bolt and remove it. Swing the caliper out and up. Remove the inboard pad and install a new pad. Be careful to not dislodge the spring clips. They hold the pads in place for reassembly. Swing the caliper back down over the rotor. Using the screw driver or pry bar, squeeze the piston in the rest of the way by leveraging against the rotor, not the new brake pad. . Swing the caliper back up and remove and replace the outboard pad with the new pad. The caliper should now fit back over the rotor. See comments below about the clips.

While the caliper is off and supported so it does not hang on the flex line, check the rotor. If the rotor shows any unusual wear, grooving or warp, it should be replaced or turned on a brake lathe. Corolla and Civic rotors are not expensive. It will save time to just replace the rotors rather than drop them off at the auto machinist or autoparts store, wait half a day or longer to get them turned then reinstall them, all while your car is out of service. Getting them both turned is about the same as the cost of one rotor. Plus, you may get a call telling you that they cannot be turned because they are worn below minimum thickness.

To remove the rotor, you need to remove the whole caliper. It requires removing the 2 17 mm bolts nearest the center hub. Now the caliper can slide straight away from the disk. Tie caliper out of the way with stiff wire to strut or spring, being careful not to stress, kink or twist brake hose. Check caliper for any leaks. Inspect the rotors for wear, grooving and thickness. Check thickness with a micrometer or take them to the parts store to have them miked. If needed, have them turned or if too worn, replaced. Thin rotors will warp easily, especially when new pads are put on and deeply grooved rotors will not allow much contact with the new pad surfaces, making brakes work harder to stop vehicle and creating excessive heat which is then unevenly distributed on the rotor, which may warp (and you will know it if it does!).

The piston side disk pad is fitted with a clip that clips into the piston. There is also a clip on the front of the caliper. Remove the clip. The new one will be supplied with the new set of disk pads. Remove both the pads, observing how they are mounted, inner and outer. Compare them to the new pads to make sure everything is the same. Clean the caliper with compressed air or dust off with a dry paint brush. Wear a mask as brake dust may contain asbestos or other harmful materials. Replace any worn parts, damaged hoses or leaky calipers.

Fit the new disk pads, first the non piston side and then the piston side. Replace the new clip on the front side of the caliper. Slide the caliper over the disk, install and tighten the two bolts. (I do not know the required torque the bolts should be tightened). Try to use the same amount of force to tighten that it took to loosen the bolts.

If you were careful when opening the bleed screw and used a hose, you will have not let any air into the caliper piston cylinder. The brakes should feel stiff at the brake pedal. If not, you will need to bleed the system to restore fluid pressure. Fluid does not compress so it will have a firm feel. Air compresses. If there is air in the system, the brake pedal will feel squishy. You will need to bleed out the air.

After replacing BOTH left and right sets of pads, you are now ready to repressurize the brake lines and calipers with fluid. With the engine off, begin pressing brake pedal slowly to the floor. Do not stab at the pedal, take a second or two to complete each stroke. If the pedal does not become firm, you will need to bleed the lines and cylinder. Have someone sit in the car to press the brake pedal. Step A, With the pedal up, loosen the bleed screw. Have that person slowly push the pedal down and hold it at the bottom of the stroke. Tighten the bleed screw. Release the pedal. Repeat Step A at least one more time. If there is a steady stream of brake fluid squirting out without any spattering or spitting, tighten the bleed screw. Now, repeat this whole procedure on the other side. Try the brake pedal without loosening the bleed screw. If you have properly bled the lines, the pedal should be firm. Remember, you may still have air on only one side so double check and bleed it before finishing up. Repeat this on both sides until you feel the pedal stiffening up indicating good hydraulic pressure. Release pedal. check fluid reservoir and add fluid back as necessary. Do not use ANY of the old fluid. Dispose of any used fluid left over safely. Cap topped off reservoir. Inspect for leaks at hoses and calipers and bulging hoses. Replace any parts that leak before attempting to drive car.

If the fluid that came out of the bleed valve screw into the container appears dirty, it would be a good idea to bleed/pump fluid through both sides to remove the dirty fluid. Compare the used fluid to new fluid. Dirty fluid will cause the piston to fail prematurely or to not release properly causing excess friction and drag. This will often wear out the pads quickly, especially the inboard pads.

If, after removing the old pads, you compare them and they are not evenly worn, the piston may be sticking. In this case, consider replacing the caliper with a rebuilt caliper. It is not uncommon for the inboard pad to wear out faster if the piston is not releasing properly.

FYI: On American made cars, there is usually a wear indicator on one pad, usually the outboard pad. It will squeal when the pad wears down too much. Murphy's Law demands that the inboard pad will wear out and gall the rotor long before the wear indicator starts squealing.

Lower car and torque wheel lug nuts. Start car. Pump brakes a few times to ensure they hold good firm pressure and are not "spongy". If spongy, air could be in lines and brakes will need to be bled again. Release parking brake. Carefully drive car around the block, making sure brakes work properly. Do not attempt to "burn-in" or "seat" brakes by working them hard early. Just drive normally and the brake pads and rotors will soon be seated well. That's It! While it seems like a lot to keep track of, over time with a few more brake jobs down, you will be able to do a decent job in about an hour.

Since you are saving a ton of money doing it yourself. Don't scrimp by reusing old fluid or cheap pads. Mid-grade pads will give you much better service.

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Q: How do I change Brake pads 1994 Toyota Corolla?
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