I recently replaced my brake pads and I could feel the pedal goes little more down for me to apply brakes. Is it normal or did something go wrong while changing front brake pads?
If you press on the pedal at a stop, engine running, and the pedal feels spongy and/or continues to compress, you may have air in the system.
If the pedal is firm but just travels a bit more, then it could be 1) the pads you installed are a little softer material than the ones you removed or more likely 2) the pads just haven’t bedded in yet and the pedal travel will decrease as the pads wear in, especially of you didn’t turn or replace the rotors.
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The pedal does not go all the way long down and nor I opened any brake fluid valve. Is there any other way the air would have gone in the system?
I did not change rotors, just replaced the brake pads. The brake works perfectly fine and I could apply brakes but it has little airy while applying brakes. I just changed the brake pads yesterday, so does it mean, it will take time to adjust with old rotors?
air gets into the system when you compress the caliper cylinder whether you have the bleeder valve open or not. Did you bleed the brakes when you were done?
You may have to press the brake pedal very hard several times while the car is sitting. That will help the caliper center itself over the rotor. Otherwise, it’s pressing hard on one side and little on the other.
Care to explain that?
Out of the hundreds of brake jobs I’ve done over the years, I have yet to have air enter the CLOSED hydraulic brake system when compressing the pistons into calipers.
Tester
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I had bleed the brakes before changing the brake pads. Do I need to bleed it again?
Ya I did pump the bread 5 - 6 times but not more… I think I will have to do more to get it aligned.
Yes, and possibly more. Did you bleed them the old fashioned way, where someone opened the bleeder while a second person pressed the brake pedal?
If so, and the pedal went down farther than it usually does under braking, it’s possible that the piston in the master cylinder traveled farther than it usually does, and picked up gunk that has been deposited on the cylinder walls over the past 7 years. That gunk can make the piston fail to properly seal to the cylinder wall, which can cause a soft pedal.
A quick, easy test for this is to start the car, don’t move it, and slam on the brake very hard and fast. Is the pedal stiff? If so, but it sinks to the floor when you press it normally, that’s a good sign that brake fluid is leaking past the piston seal – when you hit it fast you compress the fluid faster than it can leak past the piston seal, and so you get a harder pedal.
Bingo! The pads have to wear into the little grooves on your rotors. Give them 500 miles and your pedal should get progressively firmer and higher.
If you just pushed the pistons back into the calipers so you could install the new pads, no air should have gotten in. The fact that your pedal does not go all the way down says you don’t have air in the system.
That said, if you have never flushed out the old brake fluid, you are waaay past due. 3 to 5 years at the longest. Brake fluid absorbs water and it corrodes your brakes from the inside out as well as boils much sooner. - My one man quest to get people to change their brake fluid!
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If you bled the brakes before replacing the pads you may have introduced air in the system if you had someone stepping on the pedal with another person working the bleeder if the two people are not in sync. Another possibility is that you let the master cylinder get too low during bleeding and introduced air that way.
I find it much easier to use a one man bleeder Even if you use two people. They are inexpensive and you can even make one by using clear tubing that fits snugly over the bleeder and a jar. I use a very cheap one yhay has a tapered plastic needle that fits inside yje hole in the bleeder. It looks like a cheap piece of junk but works beautifully and is all a DIY needs.
It’s probably because I DIY and use the 2 man system to bleed. When we bleed after we finish, we always have some air bleed out, I was assuming that that is how the air gets in.
If you didn’t open any bleeder valves and just pressed the piston back with a clamp to make room for the new pads, then air shouldn’t have gotten into the system. But that’s not the recommended way to do it according to many posters here, especially if you have ABS, b/c doing that can force fluid backwards into the ABS module. Something it isn’t designed for. Even w/out ABS I don’t try to retract the piston on my Corolla without loosening the bleed valve first. I’ve always been able to do it that way, without having to bleed the brakes later. I attach a clear hose that runs upward from the bleeder valve first, so I can watch for any air bubbles.
In my 40ish years of being a mechanic I have never seen or heard of having to bleed the brakes due to compressing the caliper piston. Ever.
If there’s air in the lines then there’s a problem not related to caliper pistons.
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If that were true the service manual would instruct to loosen the bleeder screw when retracting the piston but it doesn’t.
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Lots of theories here, but my vote’s with @Mustangman. Drive it, carefully, for a few hundred miles. And, the brakes feel different because they are different. That was the point of the job in the first place.
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The brake rotor surface does no stay “flat” as the rotor wears, it generally wears more where the center of the pad contacts the rotor, that is why rotors are resurfaced or replaced during brake pad replacement…
Your new brake pads do not match the contour of the worn rotors. Back yard mechanics sand the surface of the old rotors to give them a rough finish, this removes brake pad material faster to seat the pads.
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Keep in mind that OP later said he bled the brakes prior to replacing the pads.