Brakes feel weak

[Mahmood07]

My car is at 60k Miles, and I have recently replaced all 4 brake pads, the rear rotors, and changed the brake fluid. Everything felt good until a few days ago, when I started noticing that the braking power isn't as strong as it used to be. I don't feel that strong initial bite anymore. Could worn front rotors make the brake feel weak, or do you guys think this could be something else like a leak? Thanks.

[1MOREMOD]

Leak is possible but would usually result in failure not just weak. Did you change pads? More likely have air bubbles in the fluid.

[bdaddylo]

Is the pedal firm or going to the floor? If it is firm, then it's most likely your pads and rotors.

[jphughan]

Sounds like you haven't bedded in your new pads to your new rotors. Until the pads have a transfer layer laid down on the rotors, they'll perform noticeably worse. You might also be experiencing "green fade" on your pads since they're brand new, which goes away with general usage.

[e1000]

also, what type of pads?

[Mahmood07]

Originally Posted by 1MOREMOD

Leak is possible but would usually result in failure not just weak. Did you change pads? More likely have air bubbles in the fluid.

My Pads look like they have a lot of life in them as they have been changed 2 months ago. The only old part of the brake system are the front rotors that have never been changed since new. They have a pretty visible lip on them, but I didn't think that would affect brake feel.

Originally Posted by bdaddylo

Is the pedal firm or going to the floor? If it is firm, then it's most likely your pads and rotors.

It doesn't go to the floor, but the brakes do nothing for the first few inches that the pedal is depressed. When I tried to do a full stop emergency brake, it just didn't feel as strong as before.

Originally Posted by jphughan

Sounds like you haven't bedded in your new pads to your new rotors. Until the pads have a transfer layer laid down on the rotors, they'll perform noticeably worse. You might also be experiencing "green fade" on your pads since they're brand new, which goes away with general usage.

I bedded them as best I could, and they were working fine for the first 2 months. It may be that the front rotors are too thin?

Originally Posted by e1000

also, what type of pads?

Stock Pads and rotors



I will be taking it in on saturday to replace the front rotors and maybe check the brake fluid. Thanks for the tips everyone.

[jphughan]

Thin rotors might be a possibility, though I assumed they'd have measured your rotors when swapping out your pads. I'm also not sure what symptoms of a too-thin rotor are. I'd imagine that would just cause an inability to get rid of heat as efficiently, but if that's the case then you'd only see reduced braking power after repeated stops that had put heat into the braking system. Any chance it's getting close to replacement time for your tires? It could be that they're not gripping as well as they'd need to be for maximum braking effect. If tires were the culprit you'd probably have ABS kicking in sooner than usual.

If your pedal isn't going farther down to the floor than usual, brake fluid wouldn't be the culprit. And even you do notice increased pedal travel, if it occurs even before you've put a LOT of heat into the brakes (it'd be very hard to boil even the stock fluid on public roads), then you've probably just got air in the system. Depending on whether the air is in the calipers (from not closing the bleed screw before releasing the pedal during service) or the master cylinder (from letting the reservoir get too low during service) you'll either just need to bleed the brakes or flush the entire system. But it won't be because the fluid is too old or not high performance enough.