Front Rotors 03 EXT

[xtremeskier97]

I had a look at the front rotors yesterday and noticed something I've never seen before on any rotor (this is the first brake job on this truck since I got it last year). The rotor actually has a lip on the outer edge and inner edge and the pad is down in it. Does this make sense? The pads have a lot of life left on them, but I think the rotors might be shot. The previous owner probably just kept changing the pads and never the rotor...or it may just be how it was designed? I dont know.

Any thoughts? Im getting ready to order some brake and suspension parts and need to know if I should replace them.

Thanks!

 

[The_Roadie]

They're designed to be flat. How much of a lip? Much more than a few thousandths would bother me, but I'm easily bothered by some things. (Not so much by others, like dirt.) A dollar bill is 4 thousandths of an inch thick, for reference. WHatever you buy, don't get Cheap Chinese Crud rotors (anything under like $40 each, I think) because they may not last.

 

[xtremeskier97]

The lip is quite noticeable. I can easily catch my nail on it on both inner and outer diameters of the rotor.

Sounds like they need to be replaced.

What would you recommend? It's a daily driver for my wife. We do no towing or off roading.

Thank you for your help!

 

[MacMan]

A lip on the outer side and inner side of the pads is normal with pad use over an extended period of time. To determine if the rotor needs to be replaced, it needs to be measured with a micrometer to determine it's thickness. There is a minimum allowable size, and if it's thinner than that, it needs to be replaced.

IMO, if the rotors need changing, do the pads too.

EDIT: 1.110 (In thousandths of an inch) is minimum thickness

 

[lint]

OK is the lip just rust .take a hammer and smack it on the lip if its rust it will come off .hit it at a 45degree angel on the edge, and just work your way around. And if they are stock rotors you need to take it off an look at the back . they are known to flake off on the back side. Not sure if its cheap rotors or the dust plate holds moisture on the back side. Rust on the lip can get bad enough to rub the caliper and make a hell of a noise

 

[xtremeskier97]

No it is not rust. There is a "valley" the width of the pad in the rotor all the way around.

 

[MacMan]

No it is not rust. There is a "valley" the width of the pad in the rotor all the way around.

Please supply pics. We're not sure what a "valley" is.

As I mentioned above, have the rotor thickness checked at the "valley".....if thinner than the figure I mentioned above, replace rotors.

 

[xtremeskier97]

Here are some pictures to help show what I was trying to describe.

View attachment 21207

 

[MDBT]

New rotor and pad time IMO.

 

[seanpooh]

What type of pads have you/previous owner have been using if you know? Metallic or semi-metallic seemed to score the rotor that deep. If you run your finger over it you can feel bump tracks, then some type of metallic pad was used. Changing them wouldn't hurt but not necessary I think. My rear rotors are like yours (141K miles/10 years).

 

[tricguy007]

If u don't change the Pads the new rotors will look like the old ones because the pads have grooves in them from the old rotors so now they may have reduced the contact area on the new flat and smooth rotors

 

[MacMan]

As I mentioned above, those rotors need to be checked for thickness, and might still be usable after being turned, but I'm guessing they need to be replaced.

Do NOT buy the cheap Chinese-made ones from auto parts places....go with GM units or you'll end-up with chatter, pulsating, etc not too far down the road.

$46 ea for AC Delco from Rock Auto, minus the 5% discount code.

 

[Jkust]

Had a similar but not quite as bad lip on the top edge on the rear 9-7 rotors I changed out last week. They were ugly and rusty oem's so I changed them out. Almost seems like the pads could be a bit bigger to take advantage of the full width of the rotor.