The shop can not figure this one out!

[Pa Goose]

The other morning I notice the left front shaking as I approached stop signs/lights. By end of the day it was really bad especially at low speeds. I figured the rotor had warped so I made an appointment for yesterday to have them turned. Much to my supprise they found the left front pads down to rivets. They only have 18,000 miles on them! Anyway they turned the rotors, installed new pads and supposedly bled the brake lines.
This morning it was just as bad as before only now it feels like I don't have any front brakes. So I figure they didn't bleed the lines after all. The thing that we can't figure out is what is causeing the shaking at low speeds. Worse at around 25 mph. The faster I go the smoother it gets.????? As I exited the highway I didn't touch the brakes and shure enough when speed got to around 40 it started shaking and the slower it got the worse it got. I can actually see the whole front end move from side to side 2-3 inches.
The shop checked out the front end yesterday and said everything was fine.
Suggestions please. Could it be the axle? rim? tire?

 

[geekinavette]

Maybe a cracked rotor? I had this happen to me on another car...except it was worse at higher speeds than lower. A crack may not be easy to spot with just a normal visual inspection.

Bill

 

[crowvet]

The other morning I notice the left front shaking as I approached stop signs/lights. By end of the day it was really bad especially at low speeds. I figured the rotor had warped so I made an appointment for yesterday to have them turned. Much to my supprise they found the left front pads down to rivets. They only have 18,000 miles on them! Anyway they turned the rotors, installed new pads and supposedly bled the brake lines.
This morning it was just as bad as before only now it feels like I don't have any front brakes. So I figure they didn't bleed the lines after all. The thing that we can't figure out is what is causeing the shaking at low speeds. Worse at around 25 mph. The faster I go the smoother it gets.????? As I exited the highway I didn't touch the brakes and shure enough when speed got to around 40 it started shaking and the slower it got the worse it got. I can actually see the whole front end move from side to side 2-3 inches.
The shop checked out the front end yesterday and said everything was fine.
Suggestions please. Could it be the axle? rim? tire?

My bet is on a seperated tire? I think the brake wear is another issue most likely needs new calipers

 

[Vettehead Mikey]

The first mistake was assuming it's the brakes, the second was 'turning the rotors'. The shop may as well just shaken a bag of petrified voodoo chicken bones at the car and 'called it good'.

Please don't go back to that shop, choose another one that recognises that C2-C3 Corvettes, and particular their brakes are very different than Chevettes or Corvairs.

I think you have multiple problems.

1) you have a shake, possibly caused by a bad tire, bent wheel, bad suspension component, etc, etc. Do, or have done basic troubleshooting to find that. Swap the tires around from corner to corner.

2) you have prematurely worn pads only on one caliper. That could be caused by a bad caliper, but more likely by a collapsed rubber flex line. Change all of them.

3) by 'having the rotor turned' you may have made matters worse by inducing some runout that was not previously there. 99.9% of time turning a rotor is a waste of time that just puts money in the hands of a garage. Corvette rotors do not warp, if anything the surfaces get gummed up with residue from cheap pads. This causes the pulsing or shake in the steering wheel when the brakes are applied.

 

[KANE]

.... The shop may as well just shaken a bag of petrified voodoo chicken bones at the car and 'called it good'...

 

[Curtis]

Sounds most like a broken belt in a tire.. Look for a bulge in the sidewall or bulge or gap between the tread patterns on the tire.

 

[Artsvette73]

Sounds most like a broken belt in a tire.. Look for a bulge in the sidewall or bulge or gap between the tread patterns on the tire.

I agree

 

[Pa Goose]

I called the place yesterday that did the work Monday and gave them a piece of my mind, they apologized and asked me to bring the car back in this morning so they could look at it. After what they have done NOT A CHANCE!! My regulear mechanic is bookedup til next week so I parked the car until he can look at it.
I have looked at all of the tires but see no bulges or evidence of separtation.
The problem came on very sudden, over a total distance of about 50 miles, so I doubted it was the rotors. Unfortunately if it is a tire, the closest place to get a new tire other than them is about 40 miles away.
I am considering filing a complaint with the BBB.

 

[Tom Bryant]

I thought broken belt in the tire from your first post so I agree with what others have said. A trip to any tire shop for a spin balance will show up the culprit. Tell them what you are looking for when you go in.

 

[big2bird]

1) I don't see flaming the place for turning the rotors. You were running on the rivets. Let it go.

2)Rotate the tires front to rear. That will tell you if it is the tires.

3)My money is worn out ball joints or such. Go to a decnet alignment shop and have it checked. You have to have some slop in the steering to get that kind of activity.

 

[KANE]

...You have to have some slop in the steering to get that kind of activity.

I have some slop in my steering (alignment), but ball joints for his scenario may be right on.

I think there could be an issue with the tires. Someone should ride next to the car and WATCH the front end. If it is a tire- it will look funny as it rolls.

May be a bent rim too- it is just off enough to notice at low speeds.

 

[crowvet]

I have some slop in my steering (alignment), but ball joints for his scenario may be right on.

I think there could be an issue with the tires. Someone should ride next to the car and WATCH the front end. If it is a tire- it will look funny as it rolls.

May be a bent rim too- it is just off enough to notice at low speeds.

All you have to do is spin the tires on a balancer You will see it right away. sometimes you can see it right on the car. Just put it on a lift and give them a spin.Usually a seperated tire will feel like a rocking motion at very slow speed. Good luck , hang in there its the pits when your babys sick:L

 

[Pa Goose]

And the winner is.....a separated belt along the inner tread of the left front tire.
My regular mechanic looked at the front brakes yesterday and said the other shop had ruined both front calipers, no choice but to replace them. He wouldn't touch them and said to take it back to the place that messed it up and make them fix it. They said they didn't mess it up and so on.....2nd Love has been there since early this morning with no word so far.
Will keep you updated.

 

[minifridge1138]

I'm just curious, but how can turning the rotors, bleeding the brakes, or replacing the pads ruin the calipers?

If you used an impact wrench on the bleed valves, but I can't think of another way.

I'm just curious what happened so that I don't do it next time i change my pads.

Thanks!