Hey all,

Dont know if you guys remember but I've been dealing with bad rotors for a while now. I noticed too late in the life of my car that they were becoming warped. I've been in time and time again to get them machined since this is the only option given to me that didnt involve draining my wallet. Now its happening again...but with my girlfriends (LaurelleSS) brand new car.

With the help of her father, Laurelle is financing the car ('07 Summit White Cobalt SS/NA) as of Dec 13th. She is not completly comfortable driving stick in traffic yet so Ive been driving her to work the past few days (15kms to get to her work). Last night I noticed that the brake pedal did not come back up all the way (maybe a cm or two shy of full release) after I let off of it. I decided to keep an eye on this. This morning I drove her again, and on the way back (getting on 407) I noticed the steering wheel started shaking. Lightly at first, then quite vigorously. At first I thought it may have been the rough surface of the 407, but it was getting ridiculously unstable. I put my toe under the brake pedal and lifted up, and all was calm again. I immediatly drove to the dealer and told them what happened. They told me theyd check it out and let me know. I go back to work and wait for the call.

I got the call later in the evening saying the car was ready...Im thinking, OK...I guess everythings alright now??? Didnt really know what to expect. I go to get the car and check the bill...
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"Job #1
Complaint: Brakes vibrating while braking HWY speeds also seems to be sticking
Cause: Roat test @ speed over 100km and rear brake rotors pulsating and noisy. Both rear brake rotors corroded.
Correction: Re & re both rear brake rotors and machine, clean parts. Do all nec. adjustments. Road test speed over 100km OK."
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Job #2 was the same but for front rotors.

I couldnt believe this was happening. How could they be corroded at a mileage of 700kms??? The car came to her with 200kms on it. There is no way her father or her are going to have something FIXED on a brand new car.

What are your thoughts on this everyone? Im going to speak to he service manager about this tomorrow afternoon. I believe these parts were faulty and should be replaced, not machined

 

thats bullshit.. i dont understand what kind of service that delarship puts out, they should really treat the customers with more care

 

Well, my SS/SC has brake issues. New pads and turned rotors = crap job by dealer. GM won't fix after I've had them turned twice in less than 500 miles.

Advice: Go aftermarket, the OEM rotors blow beyond belief. I actually found out they are universal to ALL cobalts and Ions. Shared between the coupes and sedans. wow, that explains everything..

 

Keep the comments coming guys. Didnt someone on here start some kind of petition about the GM rotors? Anything happen with that?

 

I'll dig up some of my posts about my brakes and recent work. brb

 

I work for a dealership & own a 06' Cobalt SS w/ almost 20,000 miles on it...after sitting on the lot, some rotors develope rust on the rotors. Not something that has to be machined though. If rotors are warped in that short of time, sounds like someone is riding the brake.

 

Bro **** Gm, there techies dont know how to do anything ... I swear to god those idiots cant even install a sunroof properly they fucked mine up 4 times!!!!!!!!!

do yourself a favor and find a reputable mechanic and actually get your car fixed the correct way ........yes you may pay more since you would be replacing the broken rotors however in the long run if they keep warping you will be spending more money getting the warped ones re-run......

 

if you go aftermarket and don't get slotted or crossdrilled rotors make sure you stick with wagner brake products they are the best. remember you get what you pay for

 

if ur havin a problem with the rotors..get new aftermarket ones. yes its a problem w/ a lot of cobalts/ion's. they get hot very easily and warp or rust...yep bad design. aftermarket=better. check out c/a drilled/slotted rotors.

 

https://www.cobaltss.net/forums/show...ghlight=brakes

https://www.cobaltss.net/forums/show...ghlight=brakes

Here are my brake problems... Enjoy!

 

We had problems with the brakes at 700 miles, and had GM REPLACE pads and rotors, have nearly 3000 now and no sign of problems, we had TWO VERY GOOD DEALERS WORK ON THE CAR, if you are having problems go to a different dealer.

 

Not riding the brake. Period. And these other guys arent either. GM rotors are just plain weak.

 

yeah mine were bad at 700 miles had them fixed twice then they refused so now i had to buy rotorworks brakes and they are awesome

 

Response from service manager: "We are following procedure. You'll have to call GM directly"
Looks like Ill be calling. Anybody ever called GM?

 

I have had dealings with GM dealers in both Canada and the US(Fla) and I must say I have always had good respnses from them.

Which Dealer did she or you buy/lease the car from?

Is it a leased car or an outright purchase?

I have a contact in at GM in Oshawa I can ask

 

Most of the posting traffic on this subject indicates that the dealers will first turn the rotors (which will fix the issue but it will return faster than the first time due to thinner rotors) then replace with the same stock parts (meaning they will eventually warp like the originals). My SS NA has the same problem. I have the GMPP drilled and slotted rotors in the trunk ready to install - just waiting to get the time, and another snow storm is on the way to delay me further. I decided $400 out of pocket was less hassle to me than taking the car in, driving a loaner, and getting it back knowing it will all happen again and again. Until GM admits they have a design flaw that's the best anyone will get out of a dealer.

Here in the Rocky Mountains it's not a matter of riding the brake or abuse, it's a matter of terrain and Denver stop-and-slow traffic. The brakes go through too many heat and cool cycles, and they warp. When Hollaman and Moody were running the GT-40 Ford against Shelby's GT-40, they added extra cooling ducting to try to get better rotor life. Shelby took the opposite approach, ducting heated air from the radiator to the front rotors. His idea was that the brakes cooled on the long Mulsaine Straight, forcing the brakes through too many heat-and-cool cycles. Hollaman and Moody had brake troubles at the 24 hour Le Mans. Shelby's car ran the entire race on one set of brakes. Designer should learn from this - it isn't heat that kills the brakes, it's heat-and-cool cycles. Drilled and slotted rotors run cooler over-all, so they don't cycle with the extremes of stock rotors. Not to mention the rears aren't vented like the fronts.

I'll report back to the board when I get these installed. I hope to do a "how to."

 

Contacted GM directly. Said its GMs policy to "fix" this way. She said the car was sitting for 1 year before we bought it and that must have been the cause for the corrosion. I dunno, I still say this isnt fair at all.

 

I'd go to the saleman and get them involved. Cars do sit on lots often, and batteries and brakes are commonly an issue because of this. The GMPP rotors have done very well, and the stock rotors on my and most of the guys at "the other forum" Ion's have done very well, too.

 

Lucky you

 

I have had no problems with the GMPP's but I did notice that they eat up the stock pads fairly quickly

 

You gonna take my advice and talk to sales about it, then? Or man up and get some other rotors at least?

 

i talked to gm corporate after having dealer problems and no luck there only solution is the aftermarket but thats ashame

 

I have had to take in my wifes 2.4, 3 times for rotor problems. 1st and 2nd times they machined them. 3rd time they replaced everything. So far so good. My 2.4 shakes at a certain speed but goes away very quickly. I will see how well mine go and just might get some aftermarket ones later.

 

I bought the pads listed with the disks and was told by Crateenginedepot that they're stock. I'll run them for now but might change to ceramic or Pro Stop when the need to be changed.

 

Considering the base uses a 4 bolt pattern and the SS and SS/SC use a 5 bolt, I don't see how they could be universal.