Car shaking when braking at high speeds?

[ihaveacamaro]

So about a year ago, I went into the dealership saying that my car was shaking at high speeds -- around 75-80 mph ONLY when I applied the brakes.

They said no problem, it's covered and we'll fix it. The did something to the rotors (I forget exactly what, but they said the rotors were warped) and whatever they did fixed it.

Now the same thing is happening again 1 year later. What do I do? I don't want to have to fix my rotors every year lol...

As always, any help is appreciated

[HDRDTD]

Has anybody been changing the wheels?
Sometimes if the lug nuts aren't torqued to the correct spec in the correct order, in can cause the rotor to warp.

[cleanwhiteSS]

The rotors usually warp when they are hot and you hit them with cold water. Most commonly done when you wash your car after you have been driving it. What they do is cut them. You can get them cut again or get new ones. Just be careful with the water on them when they are hot.

[firstmate]

Had warped rotor problems on my 2002 WS6 Trans Am, every 5 - 6 thousand miles they were turned. Once they replaced them, but still happened to those. I thought it was defective rotors, they asked me if it could be the way I drove. Well considering I had been driving for over 40 years and it had never happened before, I doubted that...

Anyway, the only similarity of course is both vehicles were GM, but I have not had any problems with my Camaro rotors as yet, almost 39,000 miles. Still have original tires and brakes. But figure both will need to be replaced soon... Also, I know they can only turn rotors as long as it has enough material left on them, and have no idea what exactly is involved in finding that out.

I also heard it can be caused if you tend to brake hard to slow down, as opposed to slowing gradually. Again this would have to do with them being hot when you hit them hard I guess. Sorry, probably no help but good luck!!!

[TheHorse13]

My friend had this happen. He drove his car like he stole it and I was convinced that the rotors were going to turn into liquid plasma on several occasions.

He would always brake the car very hard. Are you doing this?

Turning rotors consists of surface testing for the proper tolerance (width remaining on the rotor surfaces) and for damage to the surface itself (cuts and grooves).

That said, I would push for an upgrade to some nice vented rotors and pads.

[1Camaro2SS]

Get new rotors or slow down to 65mph. Lol

[lakers171]

honestly i would check to see if the bolts on your wheels are tight because if they are lose that could cause the shaking at high speeds so be careful i would check each wheel.

[ihaveacamaro]

Originally Posted by HDRDTD

Has anybody been changing the wheels?
Sometimes if the lug nuts aren't torqued to the correct spec in the correct order, in can cause the rotor to warp.

Originally Posted by lakers171

honestly i would check to see if the bolts on your wheels are tight because if they are lose that could cause the shaking at high speeds so be careful i would check each wheel.

I got brand new wheels and had them changed out at a wheel shop. They torqued it and everything and it might be that. How do I check if they are torqued properly?

Originally Posted by firstmate

Had warped rotor problems on my 2002 WS6 Trans Am, every 5 - 6 thousand miles they were turned. Once they replaced them, but still happened to those. I thought it was defective rotors, they asked me if it could be the way I drove. Well considering I had been driving for over 40 years and it had never happened before, I doubted that...

Anyway, the only similarity of course is both vehicles were GM, but I have not had any problems with my Camaro rotors as yet, almost 39,000 miles. Still have original tires and brakes. But figure both will need to be replaced soon... Also, I know they can only turn rotors as long as it has enough material left on them, and have no idea what exactly is involved in finding that out.

I also heard it can be caused if you tend to brake hard to slow down, as opposed to slowing gradually. Again this would have to do with them being hot when you hit them hard I guess. Sorry, probably no help but good luck!!!

Originally Posted by TheHorse13

My friend had this happen. He drove his car like he stole it and I was convinced that the rotors were going to turn into liquid plasma on several occasions.

He would always brake the car very hard. Are you doing this?

Turning rotors consists of surface testing for the proper tolerance (width remaining on the rotor surfaces) and for damage to the surface itself (cuts and grooves).

That said, I would push for an upgrade to some nice vented rotors and pads.

I don't brake hard, sure I drive it like I stole it every once in a while, but I haven't been doing it often nor do I break hard often.

If only I had the money to upgrade....

[ihaveacamaro]

Originally Posted by cleanwhiteSS

The rotors usually warp when they are hot and you hit them with cold water. Most commonly done when you wash your car after you have been driving it. What they do is cut them. You can get them cut again or get new ones. Just be careful with the water on them when they are hot.

I don't think I ever wash my car after using it. I have heard that washing your car after you just used it is a bad idea, never knew why until now though.

Cool info

[Camaro_hx]

Common problem..

- Check all tyre pressures,
- Check brake discs & pads.

[Russell James]

Runout, thickness variation in the rotors.

What causes comebacks is turning the rotors or putting new rotors on and not rechecking the runout. If there is still a little runout after the rotor is put back on, the pulsation problem will return after some time and miles.

The runout can be in the hub, rotor to hub mounting surface, rotor itself...

The way to fix it.... turn the rotors or replace if needed. Mount and torque the rotors on the hub ( after the mounting surface is cleaned). Then mount up a dial indicator and check for runout. The GM spec is less than .002 lateral runout.

Many techs skip that step of checking runout of a new or turned rotor on the car. It might have zero runout on the lathe, but torqued on the hub it may have .010" . This may not be noticeable at first, but over thousands of miles of driving it will wear back in the warped uneven thickness variation.

After a brake job, ask the tech what the - after installed lateral runout is on the new or turned rotors. If they didn't check it - it's a crap shoot if the exact same problem will return. If 6 months later they are pulsating again - they probably put it back together with too much runout.

Hitting water has nothing to do with it. It's all about assembled runout and thickness variation in the rotors.

[My 5th]

Don't assume that a tire shop knows what the correct lug nut torque is. I had my front wheels rebalanced recently at Discount Tire--they mounted and balanced the tires the first time--and I assumed they knew the Camaro should be 140 #, as they got it right the first time. But this time a new tech did the torquing, and I thought I'd better ask "What are you torquing the lugs to?" He responded "100 pounds". I reminded him of the correct value and he went to a wall chart and came back "Uhhh, you're right". Good thing I asked.

[upflying]

Do the SS owners have a rotor warp problem after cooking the brakes?
If not, this post appears to confirm the V6 brakes are marginal and under engineered for the speed capabilities of the car. GM should have installed V8 brakes on the V6 cars.

[SSOOCH]

Originally Posted by ihaveacamaro

So about a year ago, I went into the dealership saying that my car was shaking at high speeds -- around 75-80 mph ONLY when I applied the brakes.

They said no problem, it's covered and we'll fix it. The did something to the rotors (I forget exactly what, but they said the rotors were warped) and whatever they did fixed it.

Now the same thing is happening again 1 year later. What do I do? I don't want to have to fix my rotors every year lol...

As always, any help is appreciated

Dude, I remember you! You're warping your rotors!! You're riding them too hard.