Rotor question for the brake pros

**JamminWagon** · 11-18-2007, 05:45 PM

I have been getting a shimmy on the steering wheel that shows up when hitting the breaks at 60+ mph. It seems to be a heat up problem. I have taken the car on a lift and raised the front so that the tires are off the ground. Spun them up by hand and there isnt any wobble. But I did notice that there is rust on the outter rim that had flaked off in pieces. Also there seems to be a "cutout" on one rotor. I was thinking that it might be for balancing?? Here are the pics from a crappy camera phone.

At the top rear half you can see a chunk missing from the edge

Different angle

Here is the cutout that i am talking about.

another

Plenty of pad left

So any help would be appreciated, I figured out that rotors and pads are gonna cost me about $150. Plus the amount that the hobby shop will charge about 2 hours of work. So I am looking at $155 (rotor, pads and anti-squeal) and $10 stall cost. I doubt that I can get a brake shop to do it for $165.

**JamminWagon** · 11-18-2007, 06:07 PM

Also found this statement in parts manual

All brake rotors are fully coated with Geomet™, a water-soluble, environmental friendly corrosion preventive. Both the friction surfaces and the vents are coated. During initial brake applications of a new rotor, the brake pads scrub the coating off the friction surfaces, ensuring that the remainder will be rust free. Coating the vents also ensures that there will not be a loss of heat capacity over time.

Why the heck you have a "Water-soluble" on something that is exposed to water (rotors). Looks like my coating is off. The car NEVER has been in standing water.

**goldsmi** · 11-18-2007, 07:59 PM

jammin-
The shimmy is caused by a slightly warped rotor.
Had the same problem, changed rotors and pads, now all better.

I think that the 'chuck' is actually a machined-out groove that was used to balance the rotor. One of my rears had the same groove.

I did all four this way:
Slot/drilled powder coated rotors from DRT (ebay) for ~$300

http://stores.ebay.com/Design-Rotor-Tech

Hawk Ceramic pads from Tire Rack for ~$150

Install time was a couple of hours per axle.

Not the cheapest brake job I've ever done, but quality parts that perform and look great.

AL

**Padre Dave** · 11-18-2007, 08:08 PM

I bought some really nice rotors from Zeckhausen (sp?) Racing, found on this forum. I bought the Ceramic-quiet pads from TireRack as well. I just did the fronts...and I did splurge for the "look" and went with the drilled and slotted rotors.

Whole system is very solid and very quiet. Even the guys at the brake shop commented about how good the rotors are, compared with the OEM and Chinese stuff they see every day.

**fnkychkn** · 11-18-2007, 08:09 PM

the coating is like a latex paint. water soluble but you can't hose it off. over time, it will deteriorate. faster in salt areas.

the ground edge of the rotors is for balance.

**JamminWagon** · 11-18-2007, 10:03 PM

Thanks guys, I was pretty sure the cutout was for balancing, too perfect for a defect. I guess I will be calling the dealer to see if they have any rotors and pads in stock. I wish I could step up to the "better" stuff, but the $150 alone is going to be an unexpected $$$. Man I cant wait til I get my raise in Jan!

**Rob@WretchedMS** · 11-18-2007, 10:17 PM

i would avoid buying the 'cheap' drilled rotors off ebay, I've seen a few occurrences of them cracking and breaking apart.

Check with local parts stores and see if you can find Centrics (sp) rotors, (I'll check tomorrow to see if they are available) They are coated black and don't really rust due to the coating. Pricing isn't bad,

Again, i will check for availability on part numbers tomorrow.

**JamminWagon** · 11-18-2007, 10:25 PM

Originally Posted by Rob@Westfield-ET

i would avoid buying the 'cheap' drilled rotors off ebay, I've seen a few occurrences of them cracking and breaking apart.

Check with local parts stores and see if you can find Centrics (sp) rotors, (I'll check tomorrow to see if they are available) They are coated black and don't really rust due to the coating. Pricing isn't bad,

Again, i will check for availability on part numbers tomorrow.

Kewl thanks. I have read a lil bit on drilled rotors. Like only get ones where the holes are chamfered. Just drilling holes and leaving the edges straight can gouge the pads.

**goldsmi** · 11-18-2007, 11:35 PM

if you look at the DRT listings you'll see that the holes are chamfered and the slots are properly edged. They appear to be just as good as any 2X priced part.
Time will tell.

**Rob@WretchedMS** · 11-18-2007, 11:58 PM

it's not that, you can chamfer them all you want, but sharp edges are where cracks start, and you can't remove all of the sharp edges by drilling them.

The higher end stuff is molded with holes in them, Slotted rotors are a fairly dependable choice, like Powerslot or something along those lines.

Just be careful with the cheap ebay stuff, brakes are not something that i want to fail coming off the highway.

**roswald0511** · 11-19-2007, 08:50 AM

PM R1 Concepts. They are a vendor on the forum. I bought all four rotors and front and rear pads for 400 shipped. They are centric cross drilled and slotted rotors.

**SanDiegoChargerRT** · 11-19-2007, 11:38 AM

I had the same problem on my 2006 Charger RT. In my case, turning the rotors was enough to solve the problem.

**Rob@WretchedMS** · 11-19-2007, 12:36 PM

Originally Posted by roswald0511

PM R1 Concepts. They are a vendor on the forum. I bought all four rotors and front and rear pads for 400 shipped. They are centric cross drilled and slotted rotors.

That's a good price.

For the unslotted, undrilled version it's over $100 each

**JamminWagon** · 11-19-2007, 08:58 PM

Decided to stay simple, so I thought. Ordered stock rotors $135 w/tax and with military discount (10%). The not so simple part, $122 for pads!!!!! I dunno, are they gold plated??? Now I need to know what type the stock pads are?, ceramic, semi-metallic etc. I am trying to stay in the $60 range. Anyone have ideas??