brake vibrating issues

[wade]

iam having some strange brake issues with my 88. when i first drive the car the brakes work fine, but if i brake hard for two or three applications, or if i brake from a fairly high speed, i have a fairly serious vibration. iam also having trouble tracking down if it is the front or rear.sometimes the steering wheel vibrates,and other times it does not. Past experience with other cars has simply turned out to be brake rotors that need to be turned, but
this vibration comes and goes,obviously a heat issue. i have done some research into this and have been told that the vette calipers are also famous for warping, is this a problem anyone has come across?. I don't want to replace the entire brake assembly if i do not need to. so i guess i need to know if there is a procedure to trouble shoot this. a way to check the rotors and to isolate front or rear problems,iam planning on replacing the rotors and pads, but if the calipers are warped it seems like it will just be a matter of time until i destroy another set of rotors, any help would be greatly appreciated.
cheers!!!

 

[jsinga]

You have trashed front rotors.
If you don't have 13" brakes on your 88 you can get them from any 94-96 all you need is rotor bracket and caliper. The pads are the same for all 88-96 C4's

JS

 

[Eagle85C4]

I have a set of rotors and calipers for an 88 that I cannot use on my 85...could make you a deal....rotors have been turned and are in perfect shape....

 

[vader86]

I bet your rotors are warped.

 

[Dave C. '04 Z06]

makes sense

The problem is what everyone is saying... your front rotors are done.

What probably happened is they were "turned" a time or two, which thinned them out. Now they're straight but after you use them a couple of times and they heat up, then they start warping which gives the vibration. Once they cool off they go back to straight.

Buy some new rotors and you should be fine.

-Dave C. '97 Z28
1997 Camaro Z28 w/ 454cid Big Block
1995 Corvette LT-1 6-spd

 

[tyrel]

Here is an interesting site about the phenomenon of "warped" brake rotors.


http://www.stoptech.com/whitepapers/warped_rotors_myth.htm

 

[wade]

thanks for all the info, iwas fairly sure it was the rotors but wasnt
positive. i have checked the rotor thickness and the fronts are at about 19.2mm. manual says min is 18.9mm. so i would imagine that they have been turned a time or two. last thought, what makes everyone so sure that it isnt the rear rotors? like i said, sometimes even when it does vibrate the steering whell is rock solid, other times it vibrates.