Hello all, well its about that time to do a complete brake rotor and pad replacement. I have currently on my 2007 Tahoe LTZ, 180,300 miles. On the car is the 2nd set of rotors, 3rd set of front brake pads, and 2nd set of rear pads.

The original OEM rotors lasted quite a long time, and I was impressed they held up so well. I have now on the vehicle a set of slotted rotors, front and rear, which are cryo treated. And to be honest I didn't notice any difference in them at all, they still warped just like the OEM ones and I think they warped quite a bit sooner than the original OEM rotors. lol! And I am using the Hawk HPS blue brake pads, which are pretty good IMO. But beware the low pad warning indicator does not work well on these pads or at least the ones on my Tahoe don't work well, I didn't hear any squeal from them, just a rubber squeaky noise. When I just recently went to do a tire rotation last week, I went to check on the front pads and there was barely any left, I was shocked, still not metal to metal just yet.

So since these rotors are slotted, my research has suggested I can not turn these rotors. So I went out and got new rotors front and rear and new pads front and rear as well. All GM OEM parts. But I was a bit worried when I opened the box for the rotors and there was a gray coating on them, I've never seen that before. Mind you I'm a newbie to self car servicing, and when I did the brake job on this Tahoe, it was my first ever (~3 years ago), it took me about 9 hours, lol! But anyways back to the gray coating, I wasn't sure what to do with it. But after a Google search I found out it was a Zinc coating for rust prevention, so I guess I don't need all the brake cleaner I just bought for this job, is there no cosmoline (sp?) on new rotors anymore?

Wish me luck! Luckily the youtube videos I used last time are still up and running. Here are a few pics of the new rotors, and I will update with more pics of the old rotors, which are quite corroded btw.

 

wow that is very interesting, I have seen that coating before on other rotors but only on the hub area not the friction surface... I suspect after proper burnishing of the rotor and pads they will be fine, though I would give myself ample stopping room should the coating act more like a lubricant the first few stops!

 

Just in case anyone ask what burnishing is


Burnishing Pads and Rotors
provided GM Service Manual
Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

Burnishing the brake pads and brake rotors is necessary in order to ensure that the braking surfaces are properly prepared after service has been performed on the disc brake system.

This procedure should be performed whenever the disc brake rotors have been refinished or replaced, and/or whenever the disc brake pads have been replaced.
1. Select a smooth road with little or no traffic.
2. Accelerate the vehicle to 48 km/h (30 mph).
Important: Use care to avoid overheating the brakes while performing this step.
3. Using moderate to firm pressure, apply the brakes to bring the vehicle to a stop. Do not allow the brakes to lock.
4. Repeat steps 2 and 3 until approximately 20 stops have been completed. Allow sufficient cooling periods between stops in order to properly burnish the brake pads and rotors.

 

Here is the document I found, look at the bottom of 2nd page in a gray highlighted area. It says it "shouldn't" affect brake performance. I hope they are right! loL!

http://acdelcotechconnect.com/pdf/ne...-news-2010.pdf

Thanks for posting this. There are so many different variations of burnishing or bedding in. The one I did after putting the current slotted rotors on was using speed of 50+ mph. I'll probably do more research on this process to maximize it.

 

Just found this paragraph from zeckhausen.com's website:

"If you just installed rotors with zinc plating or if the rotors have an anti-corrosion phosphate coating, you should postpone bedding until normal driving has allowed your pads to polish the rotors clean and removed all traces of the plating or coating. If your new brake rotors have an oily anti-corrosion coating, clean this off thoroughly with brake cleaning spray and/or hot soapy water before installation."

So maybe I'll just take it easy for a bit until the coating is completely off. Then I'll perform the bed-in process.