Brake pedal vibration only when braking at high speeds

So just as the title says on my 2011 Nissan Sentra. Work has been done recently by me and im not afraid to say that by no means am I a professional. Work includes front struts, front brake pads and rotors, rear pads and drums. Also just replaced the rear driver wheel cylinder because it looks as if it was leaking. I am also experiencing a slight pull to the left while drive down the highway. All 4 tires have been replaced but at different times with 2 different brands/models. An alignment has come with the second set of tires and the pull is still occurring. I know this is a ton of things to diagnose but I am way too far down the rabbit hole to give up now! Please help!!!

Got an infrared thermometer gun? I bet one of those front wheels is hotter than the other after a drive. Probably the left one. If you don’t have a gun you can just touch them with your fingers, but that might hurt a little bit (nothing permanent).

Did you grease the caliper slides when you did the pads/rotors? One of the calipers might be binding.

Also, did you hang the calipers with a strap/hook or did you just let them swing on the brake line while you were doing the rotors? If the latter, it’s possible you damaged the flex line and it’s pinched internally and not allowing the caliper to retract.


would the fix if its the front left to be just simply replace the caliper?

It might be cheaper than that. You might just need to grease the slide. Or replace the flex line. You’ll need to determine exactly what’s causing the stick before you start spending money on it.

Now come to think of it one did seem to be a touch more stiff than the other one. Is it possible to replace them or would that be a completely new unit?

Replace which, the slide? Generally you need a new caliper if the slide is bad. But often it’s just not lubricated, and smearing caliper grease on it fixes the problem.

how would I tell if the slide is “bad”?

It’s rusty or pitted or scratched up.

BTW, you can replace just the slide - I’ve just usually found that by the time the slide is crapped out, the caliper’s probably in rough shape too. But if you determine that the caliper is otherwise good, you can just get the pins.

it looks like they have a slide/pin set at the local Autozone. Is caliper grease a thing or is a general use grease?

Yup, it’s a thing. You can get it when you pick up the pins. They usually have little squeeze packets of it up by the registers that are good for at least 2 calipers.

Thank you for the quick response it looks like I have 2 possible places to check for the repair. Ill report back for sure!

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Did you clean the hubs of any rust prior to installing the new rotors?

If this isn’t done, it can cause run-out of the rotors which can cause a vibration when braking.

3M makes a tool for this purpose.


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not gonna lie didn’t even think of that so I guess i have 3 things to look at when I get home today. Thanks!

Yes, replacing the bad caliper would fix the problem. There are kits (just a rubber O ring, boot and slide grease) that are around $5, but replacing the caliper is easier. I’d probably do both. If you replaced only one rear cylinder, I’d do the other. When one fails, the other is not far behind. Then you’ll be set for years w/o problems.

You may luck out and your rotor is not permanently warped. (That’s what causes the pulsing.) If it is warped, you can probably have it turned. An easy test is to use a block to steady a pencil (or similar) held just touching the rotor. As you slow turn the rotor by hand, you’ll see any warp.

so a bad caliper would cause the rotor to warp? Is that the main reason a rotor commonly warps?

Rotors warp due to high temperatures (usually). High speed could cause the warp, but it might not have a permanent warp yet.

I had a new Chevette w/ factory defective calipers. Like yours, they didn’t release. The car had 2,000 miles on it when they warped the first time.

Rotors generally don’t warp. They get uneven deposits of pad material on them, which makes the surface bumpy, but the rotor itself is not warped. After all, they’re made out of cast iron. The cooks on here will know that the least likely pan to warp in the whole kitchen is the one made of cast iron, even if you do something dumb like put it only half on to a high-output burner.

Turning them still works, because you’re cutting that pad material off (along with some of the rotor surface), but its not always necessary.

Unless the pad material is really baked on, re-performing the bed-in procedure will often cure “warped” rotors. 10 or so moderate-braking slowdowns from 40mph to not quite stopped, then 3 or so hard braking slowdowns from 40 without coming to a stop, then drive around normally for 15 or so minutes to let them cool down.

The rotors although not shiny like out of the box do not look like they have pad material on them. Hopefully the “warping” shouldn’t be an issue with this case.

Also strangely enough I am a chef…

It is the most common reason. Occasionally it’s driver caused,
such as the owner resting their left foot on the brake pedal while
driving. (This is equivalent to what happened to your rotor.)
After market “cheap” rotors are more likely to warp, if driven by
Joe Racer (lots of hard stops, close together.) Imperfections in
the steel can cause them to warp.

  Brakes transfer kinetic energy (momentum) into heat. You can

imagine the heat generated, especially when they constantly drag.
Youtube has videos.