Car Vibrating above 50 MPH After Hard Braking

['95EclipseGSX]

So I had to ram on my brakes last night extremely hard. A really awesome semi was going 40 MPH and right as I was about to pass his wheels started to drift into the left lane. Got scared he might carelessly go into the lane another foot or two and run me off the road to I decided to hit the brakes instead. I jammed them on so hard the back wheels locked up momentarily.

Now I have this vibration/low-pitched rumble whenever I drive above about 50 MPH. I tried tightening the lug nuts (they weren't lose) and pumping the brakes a bunch of times.

What is causing this? It doesn't makes sense to me that my wheels would be somehow unbalanced just by hard braking. Could one of my brake pads be messed up and rubbing against the disc? Should I try pulling all the calipers back? Is it a warped disc? I don't really know that much about brakes. What a pain in the ass. I thought the brakes were there to be used. I use them and this is what I get. Yippee!!

 

[Boostdriven]

It could be because u put some flat spots in your tires from locking them up. I've done that before being young and dumb

 

[Bud92gsx]

You could have warped a disc after slamming on them like that..Which could mean just replace the rotors and have a nice day..

There is no way to know for sure unless they get checked or you have the tools to check...

Warped rotors are easy to change tho..A hammer does wonders..

If the pads are old..Mise well just throw in some new ones while your at it..

Also yes flat spots on the tires could cause it too..Depending on how long there were locked up and sliding...

 

[jgore1989]

i had this problem once and it was my caliper sticking

 

[airmail96]

Sticking caliper you would be able to smell brakes or see smoke, I would think.

 

['95EclipseGSX]

They were not locked up bad at all.. For 1 second at most. I locked them up way worse one time just testing the brakes and that didn't do anything. As for warped discs, wouldn't that only show when I used the brakes? This vibration/low noise happens just driving around. Basically it feels like what the car feels like when the wheels are out of balance but I don't see how that's possible. Pads are not warn out, just replaced them within the last year. jgore, when you had the stick caliper did your brakes smell/smoke? I don't have that happening...

 

[airmail96]

Where does it feel like the vibration is coming from? It could just be coincedence, but being that it happens at a certain MPH it could be a driveline problem possibly the driveshaft or something.

 

[Colt4G63 also]

One second locked up is a long time; you probably have flat spots on your tires. The same thing happened to me before when a dump truck cut me off. It's a bummer, because all you can do is ignore it or buy new tires.

The guy was driving 15 below the speed limit forever, but when I decide to pass he swung a hard left to stop for ice cream. I locked them up hard in my huge B-van and had to come to a full stop from 45-50 on the left shoulder. My tires still thumped when I sold the van years later.

 

[herms99gst]

If u have a caliper sticing u wont necessarily have smoke coming from your brakes, but u would smell them more than likely. Your tires prob do have flatspots now, and u could have posibly warped a rotor but i would think it would take more than one time samming on your brakes to do this. Take alook at the color of your rotors, if their dark blue an glazed their more than likely warped. Before u go purchase new ones see if they can be turned. To seeif your calipersor sticng, jack your frnt end up and spin both front tires, they should spin with very little trouble. If one is extremly hard to turn, u hav a stuck caliper

 

[Sleeper1gfwd]

Warped rotor with a sticky caliper

 

[GREEN4G63]

Flat spot on tires for sure.

 

[aj2494]

If a rotor is warped, that could easily cause this. When the rotor rotates, it could be making contact at a certain point in the revolution, causing a vibration. An odd comparison, I know, but I had this problem on a bike once. Not a rotor, but you get the idea.

Either this or flat-spots on your tires seem like the most likely to me.

 

['95EclipseGSX]

So if I jack the car up and twist my wheels would I be able to discern weather or not it is my brakes rubbing?

It seems like there's no way to tell if it's the tires aside from getting a new set and seeing if that solves it so I'll just have to assume I permanently damaged my $650 tires if nothing is rubbing... Jesus I am pissed at that driver right now!! What a wonderful holiday gift from an ignorant gentleman in a large truck. I should've just passed him.

 

[4g63tc]

If the Tires have flat spots, and are fairly new, i hope you got the "road hazard" warranty, go get them checked out, and they may or may not replace them outright, or prorate for new ones.

eventually the flat spots will wear out, and the tire will round itself out again. been there done that.

 

[dsmtwins2g]

I'd eliminate the other possbiltys like sticking caliper,warped rotor before buying new tires.

 

['95EclipseGSX]

Yeah I don't think I'll buy new tires. Can someone tell me exactly how to eliminate the possibility of a warped rotor/stuck caliper?

 

[herms99gst]

I did in my other post.

 

[jgore1989]

i took my caliper andtried to compress the piston. one went in no problem and the would budge

 

['95EclipseGSX]

Looks like it's my tires because the brakes are fine. I can even feel a little bit of a flat spot on 2 of my tires. So sad... Oh well. I hope the flat spots come out as I drive more. These tires have about 15,000 miles left on them so I'd hate to junk 'em.

 

[herms99gst]

That sucks man. Sorry to hear that.

 

[eligst21]

Did you check your rotors. I would hate to think that after braking like that, it would cause the tires to be able to cause that much of a flat spot to make the noise youre describing. I would say turn the rotors or buy new ones. Cheaper then tires and probably the problem. Also might as well put new pads in there as well.

 

[toadamine]

You flat spotted your tires... time for a new set...

 

[TrevorS]

These days, turning rotors tends to be more expensive (or unavailable) than replacing them. I suggest being sure your rotors are good before replacing the tires. My own solution was to clean the rotor surface (pads can leave uneven disk residue that results in pulsing brakes under even mild braking), but compared to replacing the tires, first definitely replace the rotors.

 

[DSM1G90]

Nah..just have them turned -foolish to replace rotors unless they are worn down past the min requirements for safe braking.

Pads are always in contact with the rotors and just .5mm of warpage will cause the vibrations.

 

['95EclipseGSX]

Well wouldn't the vibration get worse when I braked if it was my rotors/brake pads? There is no difference when I brake.