cracked rotor

[LimeNine]

last Saturday I was driving at highway speeds when the left front started clicking, I thought it was a wheel bearing


HEY Jazz lets do some inspecting


Wholly mackerel the rotor got hot enough to crack


sigh


I suspected that caliper was sticking, burnt rotor,


I ordered the remanufactured stock type caliper ($42), cuz I'm not rich


parts arrived today, but while I was waiting for them during this week, I stopped at a famous nationwide brake specialty place - the guy wanted to know if it is a 6-speed or an automatic LOL, I tried to not become an arrogant customer - anyways they quoted me $310, just for the one front wheel . . . . Pffffttt, as we see here the lower piston obviously has been stuck for some time, except the outside pad looks parallel, even wear, this pad was on the inside, I couldn't see this amount of wear until now


nothing dramatic here, just some $63 thermo quiet pads


again - nothing dramatic, just a $29 stock type vented rotor (disposable)
I remember when rotors where so valuable that you turned 'em to achieve a smooth surface, but for $29 who wants to waste time turning rotors?


I'll take the wheel back off and paint the caliper, just had to test drive it after bleeding


I like these cheap stock brakes, I also have a Chevrolet Tahoe, and recently replaced the brakes on it, but still a Heavy vehicle -

and Yes, brakes feel great compaired to the Tahoe, I'll save ya agony of viewing the driver side pictures - it got a new rotor and the other set of those thermo quiet pads - and umm, the brakes on my sportbike are superior compaired to either of my "cages"


I like doing this stuff, saved a load of cash
I could've saved even more if I had opted for the disposable caliper,
but I fear the quailty and the origin of such a cheap caliper

[35th-ANV-SS]

Nice pics. I've seen a cracked rotor before. Pretty scary shit!

[c5z28]

Never seen one crack like that before. Holy crap!

[Too Fast]

So what did Jazz think of all this?

[blue02Z]

hey man just an fyi everytime we put aftermarket rotahs on a car we turn em before because they are 97% of the time warped. also wagner pads suck. haha sorry man for busting you bawls on your parts but i am glad to see that you did it yourself instead of paying a shop to do it. congrats man, lots of peeps just take it to "just brakes" and get raped or low quality work

[LimeNine]

wow, never thought of the disposable rotors would be warped, they seem fine when driving, yet I didn't mount 'em to a lathe and check the TIR (total indicator reading). maybe I got lucky?
What would an acceptable TIR be on a rotor?

no offense taken, but please explain your experience with wagner brake components.

Oh and the Jazz, she thought nothing of the whole noisy car thing, she was more interested in barking at absolutely nothing at all.
Silly Dog.

[Mr. Luos]

Looks like the pad wore because of the cracked rotor. I doubt it just cracked overnight....probably had sections creating funky wear for a while.

Burnt rotor is because of the limited amount of friction those pads were giving the rotor.


Mileage any better?

[Too Fast]

wow, never thought of the disposable rotors would be warped, they seem fine when driving, yet I didn't mount 'em to a lathe and check the TIR (total indicator reading). maybe I got lucky?
What would an acceptable TIR be on a rotor?

no offense taken, but please explain your experience with wagner brake components.

Oh and the Jazz, she thought nothing of the whole noisy car thing, she was more interested in barking at absolutely nothing at all.
Silly Dog.

Silly dog indeed!

And I don't know why, even a cheapy rotor, would have thickness variation. TV is what most people call a warped rotor, causing pulsation when braking.

You shouldn't have total indicated runout of more than ~.005" for a satisfactory braking experience. As far as thickness variotion goes, the spec for it is ~.0005". If you give it some thought, warped rotors don't cause much of an issue unless it is huge, since 99.8% of cars on the road have floating calipers instead of fixed. So, the caliper "floats" with the warp, unlike a fixed mount caliper (think late 70s and earlier Corvettes).

In my work experience, I've had to reface the rotors off the shelf probably 5 times in over 25 years. And I've done many, many brake jobs!

[Smittro]

Looks like a caliper pin issue started to me.... Possibly causing it to hang and over heat the rotor.. Ask me how I know.....

[LimeNine]

I was wondering the same thing about mpg,
because I had a 2001 Ram Air T/A back then and it got 26mpg,
this '98 Z28 has only gotten 24mpg.

I haven't driven it much since replacing the brakes,
I'll have to check the mpg during the next fill up.
might be awhile . .

I replaced the pins, I wasn't going to change them because they had a nice slick feel, plenty of lube, and the dust boots seemed
perfect. . . . I had separated one of the old dust boots from the old pin, and ended up installing the new pins with new dust boots.

Thanks for the TIR specs, except I'm satisfied with the way they are, doubt I'll mess with an indicator to check 'em
I am interested in the thickness issue you mentioned, wish I had checked 'em before I installed 'em. . .
I'm too lazy to take the wheels off again to check 'em,
and like you said they are floating disc brakes, and they feel fine the way they are now.


On a side note, I had a wheel once that was close to 0.040 TIR lateral runout,
real pain to balance, remounted tire, tried to tweak it or bend it to get it to balance.
ended up using a BUNCH of lead weights.

[Too Fast]

Well, you got better mileage in the WS6 since it has Ram Air. Enuff said.

Seriously, were they both AT cars, or both MT cars? Manual will get better mileage.

[Mr. Luos]

I was more or less joking about the mileage thing....


I don't know. I didn't drive the car....but it doesn't appear that is was a sticky caliper here. At least to me.
Not the way the pads were worn down.