LSJ PUP

Looking for possible explanation for this. The car shows similar vibration that you would undergo when your rotors are warped, but at much stronger level. Checked the brake pads and they have plenty of life. Rotors are gm drilled and slotted. They are 1 year and 4 months old as are the pads. Newest mod to the car are the sportline springs. Springs have been on for a few months now. My only thoughts here are that the stock shocks have gone bad. I beat on the car around corners fairly often. We checked the motor and tranny mounts and they look fine. Any thoughts?

BigTizzle903

I'm thinking the rotors are warped. Even though they are drilled and slotted if you brake hard enough for long enough they're bound to have problems eventually. Only other thing I could think of is if you got new wheels/tires they are out of balance (and yes, tires can be out of balance and you just have to drive to break them in)

krazycobalt

I would diagnose this as warpped rotors!!!

LSJ PUP

Don't think it's a tire balance issue as the vibration is only present under breaking at medium to high levels. I was really leaning toward warped rotors but because of the severity of the vibration, I began to think there was a different problem. My oem rotors warped and a vibration was present, but nothing of this magnitude. I was be completely surprised if GM would put there name of a better rotor than oem, but worse in terms of it warping to this degree over such a short period of time. Not ruling this out by any means though.

qwikredline

check your pads if the pad srface is shiny they are glazed, take a sanding block with some 320 grit and remove the glaze + get rid of drilled rotors...

steddy2112

iTrader: (1)

THANK YOU!

mrsilent13

serioulsly sounds like warped rotors

originaladrian

x2..

mrniceguy8211

Yea, my GM drilled and slotted rotors warpped on me. Both rear one's... they really suck LOL. I and just waiting for the pads to wear out and then I am putting Power Slot's on. Same thing with me though, Medium to Heavy braking is when I get the Vibes

shadowfaxss

iTrader: (3)

It is DEFINATELY, 100% CATAGORICALLY ROTOR WARP!!!!!!!! A dial indicator will reveal for sure.

BoostinLSJ

also check the abs system that would make the brakes pulse and shake under all braking my 06 ss/sc did it

BigTizzle903

That's a good point. I would also check that. Maybe it's just the ABS kicking in unnecessarily.

originaladrian

theres a big difference in feel between those.


ABS feels like ur brake pedal pulsating, consistently, and usually only under hard braking.



warped rotors= vibrations, car vibrates not just pedal. its annoying and u can DEF tell the difference if u have ever felt ur ABS kick on.

laserblue2006

bada bing bada boom

LSJ PUP

I guess I'll have them cut after I check the pads. Of the problem comes back after that down the road, which it will, I'll replace them. There should be a disclaimer when you buy these rotors, something to the tune of; the rotors will warp in a little over a year because they suck.

mrniceguy8211

There is a diclaimer right above the parts counter. You just cant see it when they are bending you over on the price. I payed $300 for these pos rotors. GM lets me down again LOL

Maven

iTrader: (1)

I agree excpt its not likely they are warped.(put that in your collective pipes and smoke it)

There is, its called research. On this site and on all quality brake rotor company sites, you will almost NEVER see drilled rotors billed as a true performance rotor, and you will see many knowledgeable recommending to aovid them like the plague unless youre a show car.

rocketpunch1221

Those drilled metal rotors are more for show than for go. I think most of those rotors came with a disclaimers saying not for track use. Cracks will develop around the drilled hole, especially on low quality disks.

AlphaJaguar5

Guys, they are not warped.

Any other suggestions?

Qwik: Thanks for the suggestion we'll try that.

qwikredline

Alpha buddy happy to help. I was gonna say "snow in the wheels" as you are a semi pro hockey player and may be the hockey rinks are unplowed, but then i said to my self: "Self, Corey lives in FLORIDA" Ooops....

BigTizzle903

What about slotted rotors?

Dave7417

It almost sounds like pad imprinting, sometimes called hot spots.

Have you been running fast, then hard on the brakes as you hauled down hard to a dead stop? Like a stoplight? Did you keep pressure on the brakes, to hold the car in place? (Is your car an auto?)

If you get the brakes hot enough, and come to a complete stop still applying heavy pressure on the pedal (without letting the car roll a little,) some of the brake pad material can literally fuse to the rotor resulting in an uneven surface. This can cause subsequent braking vibration, and not always show up as runout on a dial indicator.

Maven

iTrader: (1)

Ive never seen a car with a rotor related pulsation that had rotors that measured within spec.

If the problem is caused by the rotors, youll be able to measure it.

LSJ PUP

I'm leaning toward it being the pads as qwik is suggesting. (Thanks by the way in case Corey didn't pass that along) The rotors look perfect and I don't see or feel any of the glazed ridges that I observed on my OE rotors. Granted I'm not a human dial indicator.

originaladrian

u did gauge the rotors correctly right??

im going to say 99% of the time by looking/feeling the rotors you will not notice anything.