Dodge Challenger Forum banner
  • Hey everyone! Enter your ride HERE to be a part of September's Ride of the Month Challenge!
1 - 10 of 10 Posts

·
Registered
Joined
·
128 Posts
Discussion Starter · #1 ·
I recently installed drilled and slotted rotors on my 2010 RTC.
When applied they make a very peculiar noise.
Like a drone or humming sound that the stock brakes/rotors did not.
Is this normal?
The rotors are directional and are installed correctly.
 

·
Registered
Joined
·
128 Posts
Discussion Starter · #3 ·
Yes ,followed the instructions that the seller included with the purchase.
Any other thoughts or ideas are appreciated.

Thanks
 

·
Registered
2016 R/T Scat Pack
Joined
·
1,522 Posts
Mine almost sounded metal to metal grinding when in the rain on a first stop but were quiet otherwise.
 

·
Premium Member
Joined
·
3,072 Posts
I put drilled and slotted rotors on my truck which had smooth rotors originally. The drilled/slotted make what I would characterize as a "roaring" sound or similar to when you go from smooth blacktop to concrete road.
 

·
Registered
Joined
·
128 Posts
Discussion Starter · #6 ·
Did you seat the pads correctly?

Sent from my SM-G975U using Tapatalk
Yep, followed the instructions to the letter.

I put drilled and slotted rotors on my truck which had smooth rotors originally. The drilled/slotted make what I would characterize as a "roaring" sound or similar to when you go from smooth blacktop to concrete road.
Waumo, thanks for replying.
Do you know what causes this sound?
 

·
Premium Member
Joined
·
3,072 Posts
Waumo, thanks for replying.
Do you know what causes this sound?
I can't explain the physics of why they make noise but if you think about sliding a flat surface pad over a grooved rotor under tremendous pressure it is not hard to see it could make noise. I you do a search for "why are slotted rotors noisy" you will see posts on many different forums about the "problem" and a lot of conjecture about the cause.

I suspect the drilled (holes) may make more noise than the slots but that is just a guess.
 

·
Registered
2020 Dodge Challenger Hellraisin Scat Pack
Joined
·
4,205 Posts
I recently installed drilled and slotted rotors on my 2010 RTC.
When applied they make a very peculiar noise.
Like a drone or humming sound that the stock brakes/rotors did not.
Is this normal?
The rotors are directional and are installed correctly.
Have had a few cars over the years with drilled or slotted rotors. Do not recall any with both features present.

At any rate I never noticed any noise from the brakes. (The noisiest brakes are the rear braks of my M-B Metris cargo van. At low speed -- when backing out of a parking space -- with light braking they are pretty noisy. But they are solid rotors. At higiher speeds the brakes do not emit any real noticeable or bothersome noise.)

If the slots are not angled correctly this I could envision result in noise. The slot and pad want to "meet" with some angle to "ease" the slot under the pad (was "rotor"). Thus one sees rotors with slots that are machined on a diagonal to the direction of rotation. I do not recall ever seeing slots machined radially from the center out.

On this subject if the rotors are marked R/L is it important to install the rotors on their respective correct sides.

Drilled rotors...Often the holes are cast in. If solid rotors are drilled this can give rise to cracking. With cast in holes the rotor is less likely to crack. A problem though is the cast in holes after the rotor is machined to its nominal thickness present a bit of harder metal in the form of the cast iron surface of the hole which will ruin the pads in no time. To avoid this the holes should be chamfered to put the cast iron surface of the hole below the rotor's surface so the pads never contact this.

If a hole or holes were not chamfered or something got caught in a hole this can cause noise As an aside I bought a used car with drilled front rotors. The previous owner washed the car all the time. One problem with this was the holes had some build up of rust/brake dust. I had to take a round coarse file and clean out every hole of both rotors. While this build up didn't make any noise it prevented the holes from doing their job as effectively as they would if clean.

Also, as with slots the holes want to in a pattern than doesn't present an abrupt line of holes all at once to the pad. The holes want to be staggered. I'll post a pic of the front rotor from my Porsche 996 Turbo that shows what I mean:

Product Steel Kitchen utensil Rim Small appliance


I suppose another pblem could be if the slots (or holes) are too large. Not sure what the limits are but at some point if the slot is too wide the pad could "fall" -- or be pushed remember it is being forced against the pad by considerable pressure -- into the slot.
 

·
Registered
Joined
·
1,528 Posts
I installed R1 Concept slotted and drilled rotors on my 2016 Scat Pack in the first year and they have been trouble/noise free 70k miles later. I originally had the Z76 pads but switched back to Wagner ThermoQuiet Semi-Metallic. Yes I have to clean the wheels more but I like the bite better then the Z26. Honestly the Z26 is fine for daily driving but in extreme stopping situations I didn't like them.

1005426

1005427
 

·
Registered
Joined
·
80 Posts
I recently installed drilled and slotted rotors on my 2010 RTC.
When applied they make a very peculiar noise.
Like a drone or humming sound that the stock brakes/rotors did not.
Is this normal?
The rotors are directional and are installed correctly.
Just my 2 cents on drilled rotors. I ran them on the street; they were fine. Didn't notice any particular noise. (Power stop parts). However, when I ran them on the road course one weekend, I found the ceramic pads sucked. Switched to some good Hawk Race pads, which had good bite and they performed well, but then had a huge vibration because the rotors cracked. Bottom line, don't run drilled rotors on the road course, stick with regular smooth, or just slotted, like the slotted Brembo rotors I'm running now.
 
1 - 10 of 10 Posts
Top