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GT500 caliper question


car dude
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I have a 08 a GT500. I had the baer two piece rotors on it when my breaks started pulsing. So I put my stock ones back on and about six months later they started doing the same thing.I am thinking I might have a sticking caliper. Are the stock calipers rebulidable? I do not track the car its just a daily driver. Thanks for any help

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Are you torquing the lugs with a torque wrench in a couple of steps?

 

Tom

Not all the time. the last time the wheels were off the car the tire shop did them and they used a torque wrench. I should clarify when I apply the brakes I get a back and forth shake in the steering wheel.I have not had the chance to see if the rotors are warped but I am fairly certain they are.the car is not driven hard and the brakes have never been used to there full potential so that is what is leading me to think I might have a caliper that is not fully releasing. The only time the steering wheel shakes is when I apply the brakes. Thanks for the help.
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I had the exact same thing, but with OEM brakes and it was warped rotors. No track time just spirited driving. I don't know if I heated em too much on a single occasion, or if they were not tempered right from the factory but replaced the rotors and it was like driving on glass even when braking. Completely fixed it.

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I had the exact same thing, but with OEM brakes and it was warped rotors. No track time just spirited driving. I don't know if I heated em too much on a single occasion, or if they were not tempered right from the factory but replaced the rotors and it was like driving on glass even when braking. Completely fixed it.

Thanks I am concerned that I warped two sets of rotors. It has to be a sticking caliper at least that is my best guest I don't want to invest any money in new rotors until I can figure out what's going on. I guess I will have to take it go someone who can figure it out.thanks

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Have you ever flushed the brake fluid? Contaminated fluid can cause a caliper piston to hang up.

 

No I have not .but I will definitely put that on the list of things to do. Do you know anything about the stock GT 500 calipers? Are they rebulidable or can you service them? Thanks

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A fellow GT500 owner/friend wanted to get his Brembos checked out. He contacted the factory and they referred him to a USA rebuilder. I think it was in California. You can obtain the seals and rings to rebuild the caliper yourself. Even Rock Auto has them. If you haven't had the rotors resurfaced you might want to try that and the fluid flush first. If rotors get an uneven build up of brake material transfer, it can cause symptoms similar to pulsating.

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Not all the time. the last time the wheels were off the car the tire shop did them and they used a torque wrench. I should clarify when I apply the brakes I get a back and forth shake in the steering wheel.I have not had the chance to see if the rotors are warped but I am fairly certain they are.the car is not driven hard and the brakes have never been used to there full potential so that is what is leading me to think I might have a caliper that is not fully releasing. The only time the steering wheel shakes is when I apply the brakes. Thanks for the help.

 

This may sound a little strange, but have you tried, as someone else called it, and "Italian" brake job? Make 3 or 4 hard stops from about 60 MPH down to about 5 MPH without kicking in the ABS. This will help clean up any built up pad material on the rotors.

 

From a number of things I have read, there really is no such thing as a warped rotor. The warped rotor syndrome comes from an excess build up of pad material on the rotor.

 

Mark

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A fellow GT500 owner/friend wanted to get his Brembos checked out. He contacted the factory and they referred him to a USA rebuilder. I think it was in California. You can obtain the seals and rings to rebuild the caliper yourself. Even Rock Auto has them. If you haven't had the rotors resurfaced you might want to try that and the fluid flush first. If rotors get an uneven build up of brake material transfer, it can cause symptoms similar to pulsating.

 

This may sound a little strange, but have you tried, as someone else called it, and "Italian" brake job? Make 3 or 4 hard stops from about 60 MPH down to about 5 MPH without kicking in the ABS. This will help clean up any built up pad material on the rotors.

 

From a number of things I have read, there really is no such thing as a warped rotor. The warped rotor syndrome comes from an excess build up of pad material on the rotor.

 

Mark

 

Thanks guys I had a talk with a mechanic friend of mine. I don't like asking him about this stuff because it takes him from his work he will help me out and then won't accept any money. But I was stump so I caved in he seems to think that there might be a few things going on. He thinks since the brake pedal does not forth only the steering wheel shakes back and forth I might have a ball joint or a tire rod end that is going bad. We. are going to put it on the lift some things time this week and go through everything you including putting a dial indicator on the rotors. I will keep you posted.

 

PS: I did a little research and found the the gt500 have a issue with the A arm ball joint.

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Have you ever flushed the brake fluid? Contaminated fluid can cause a caliper piston to hang up.

 

I just added this on another GT500 site where an owner was changing pads and asking about pushing the caliper pistons back into the caliper(s).

 

Here is a copy and paste of my reply in that discussion less than 1 hour ago.................

 

------------------------------------------------------------------------

 

I agree with opening a bleeder. Unless an owner is on top of their brake system maintenance and keeps it flushed and filled with clean fluid as needed/recommended, pushing the brake caliper pistons back into the caliper with the system closed is only going to force all of the contaminated/rusty fluid back into the master cylinder.

 

All of that nasty/rusty tea colored (or even worse) fluid is also in the ABS system...............YUCK!

 

If your brake fluid looks like "pee", you are in good shape, if it looks like "tea" or even worse "root beer"............Rusty contaminated fluid......

 

At 600 original miles I added the Baer Extreme upgrade to the rear of my 2008, this is the fluid that was in the system............

001_zpsiavmwxzc.jpg

 

and the Rust settled in the bottom when the bottle had laid on its side............

 

002_zpsleechnr3.jpg

As I mentioned, that was 600 original miles and it was already looking like tea, and visible rust contaminants in the bottom of the bottle. <<Over time, that rust works great with rubber seals in the alum. and/or stainless master cyl. and caliper piston bores!

 

Before I did any rear brake upgrade, I completely flushed the system of the contaminated fluid and then installed the parts, and then bled the new parts.

 

----------------------------------------------------------------------------------------

 

My days of C3 Corvette ownership taught me about brake systems and the importance of keeping them maintained. Unfortunately, silicone brake fluid is not recommended for our ABS brake system, so we only have the moisture absorbing DOT 3, 4 and 5.1 fluids to choose from, and of course moisture (absorbed in the fluid), rusts the brake system from the inside.............Very expensive over time, especially with the ABS...... : (

 

 

 

R

Edited by Robert M
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I just added this on another GT500 site where an owner was changing pads and asking about pushing the caliper pistons back into the caliper(s).

 

Here is a copy and paste of my reply in that discussion less than 1 hour ago.................

 

------------------------------------------------------------------------

 

I agree with opening a bleeder. Unless an owner is on top of their brake system maintenance and keeps it flushed and filled with clean fluid as needed/recommended, pushing the brake caliper pistons back into the caliper with the system closed is only going to force all of the contaminated/rusty fluid back into the master cylinder.

 

All of that nasty/rusty tea colored (or even worse) fluid is also in the ABS system...............YUCK!

 

If your brake fluid looks like "pee", you are in good shape, if it looks like "tea" or even worse "root beer"............Rusty contaminated fluid......

 

At 600 original miles I added the Baer Extreme upgrade to the rear of my 2008, this is the fluid that was in the system............

001_zpsiavmwxzc.jpg

 

and the Rust settled in the bottom when the bottle had laid on its side............

 

002_zpsleechnr3.jpg

As I mentioned, that was 600 original miles and it was already looking like tea, and visible rust contaminants in the bottom of the bottle. <<Over time, that rust works great with rubber seals in the alum. and/or stainless master cyl. and caliper piston bores!

 

Before I did any rear brake upgrade, I completely flushed the system of the contaminated fluid and then installed the parts, and then bled the new parts.

 

----------------------------------------------------------------------------------------

 

My days of C3 Corvette ownership taught me about brake systems and the importance of keeping them maintained. Unfortunately, silicone brake fluid is not recommended for our ABS brake system, so we only have the moisture absorbing DOT 3, 4 and 5.1 fluids to choose from, and of course moisture (absorbed in the fluid), rusts the brake system from the inside.............Very expensive over time, especially with the ABS...... : (

 

 

 

R

WOW and this sucks I have 51000 miles and I have never had the fluid flushed. Thank you for posting this I will update when I get it on the rack and I will definitely have the system flushed.

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WOW and this sucks I have 51000 miles and I have never had the fluid flushed. Thank you for posting this I will update when I get it on the rack and I will definitely have the system flushed.

 

It is a system that is commonly overlooked, out of site out of mind. The brakes work, no worries. << In the meantime, the system is deteriorating from the inside and most everything is going to be costly, front Brembo's, ABS module and I would guess that the master cylinder is also specific to the GT500, first with the large reservoir variation and later (mid-2008 or so) with the small reservoir variation.

 

............and every time the pads have been changed, the pistons get pushed back into the calipers and that nasty/rusty fluid gets pushed back into the M/C reservoir only to be pumped back through the M/C bore and seals and back into the system as the pads wear and the caliper pistons extend. In the meantime, you check the brake fluid level and wonder..............why is my a fluid dark color?

 

If you happen to remember, please have some of that old fluid pumped into an empty clear water bottle and seal the lid. It would be interesting to see what your fluid looks like with a few more miles and age on it.

 

 

 

 

R

Edited by Robert M
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In general, brake fluid can last forever and not cause issues. Don't take that wrong, I believe in flushing mine. If you even do one track day, flush 100% of your stock fluid out of the system and use a quality replacement. If you are hard on brakes while tracking, you need to look for a higher temp brake fluid.

 

Rotors do warp, they are measured when turning them (if you choose to) Some of the issues are related to the break in after a brake job, or, lack thereof

 

Back to the OP. Let us know what you find. Troubleshooting over the internet is a bit hard

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  • 2 weeks later...

Sounds like warped rotors if you feel it in the wheel. If the wheels are not torqued properly in steps, it can warp the rotors. I would be tempted to get a new set from one of the online discount dealers.

 

NEVER push old fluid back into the caliper. This can cause damage to the ABS unit. Dump the old fluid into a container as you compress the pistons and then put your new brakes in. Do NOT start the car and push the brake pedal. Leave it off and slowly push the pedal down a few times to seat the pads. Check fluid. Then, properly bleed the brakes and again add fluid. You do NOT want the fluid reservoir to get empty. After getting a decent pedal you can start the car and check the pedal.

 

Tom

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Ok guys I have not forgotten I just have been busy and waiting on parts this came I. TodayIMG_20160118_132440382.jpg

 

I still need brakes pads and fluid and the dust seals for the calibres. Can someone explain the process of replacing the brake fluid? And what type should I buy? Thanks

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a couple ways to do it. If you have a machine, its easy. If not, you need a buddy. Start at the farthest break from the master cylinder, the passenger rear and bleed the brakes until the fluid runs clean, go to the drivers rear, then passenger front, then drivers front. There is not as much fluid as you might think. Make sure there is always fluid in the cylinder. If it goes dry, you will have air in the system. By quality brake fluid.

 

Make sure you use a torque wrench with those rotors or that can warp them. When done, drive the car slowly at first and apply the brakes. Go progressively faster until your almost in panic mode, that should seat the pads and avoid warping. I'm sure I missed something so boys, chime in

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OP, highly recommend you invest a few bucks and get a Motive power bleeder if this is a DIY job. I've done lots of brake work and this saves time, makes way less mess and ensures no air is getting in the system.

 

For street driving, Motul DOT 5.1 brake fluid works great, last a long time and is cost effective. If you road course, you build up a lot of heat, so Motul 600 or 660 or Castrol SRF are better choices. NEVER use DOT5 (silicon based) brake fluid.

 

If you are driving your car on the street, AutoZone CMAX (or they may be called 'Gold Plus' now) pads work great, make way less dust than stock and are friendly on the wallet. If you go on a road course or autocross, you will want a different pad.

 

Make sure you "bed" in the new pad\rotors properly to prevent noise, uneven wear and to get the best performance. 3x 30-5mph, 3x 55-5mph HARD braking (do not do a full stop) and let them rest...they will smoke like crazy for a few minutes.

 

I wouldn't freak out too much on the dust seals unless you drive in a very rainy or snowy area. I road course my GT500 several times a year the dust seals totally melted away. I see occasional rain days and the piston are in great shape when I change pads. If the car sees lots of rain\snow, you may want to consider the dust seals, but otherwise, it may be a waste of time.

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Thanks guys. We have NOLA Motorsports parkhttp://nolamotor.com/

 

And I really would like to do a few track days nothing serious they have track day light days and it allows the novice driver to get to know the track and his car. I appreciate the help and will keep things updated

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