Pad/Rotor Replacement? Should I go Drilled/Slotted.

I guess I’ll be the iconoclast and say that drilled and/or slotted rotors do work better in some circumstances.

I’ve got drilled rotors on my Mercedes, the 2002 V70XC and the 2001 V70 T5. Better brake cooling under hard use was the intent, but what I notice is quicker bite in the rain and in slushy/snowy conditions where moisture gets on the rotors*. There is a path for the water to be squeezed out. No weird noises. No cracking. Long life. All good.

I’ve got slotted rotors on the 2002 V70 T5. Yep. Weird whoosh noise under heavy braking, but again, in wet, particularly, freezing wet, there is better initial bite. Also, and I didn’t expect this, longer rotor and pad life. I got 100,000 miles out of my first set of front slotted rotors. The slots allow the pads to stay clean, and avoid embedding tiny bit of debris. Very smooth, even wear was the result.

I liked them so much, I bought another set for the car.

For the performance increase in adverse conditions, and the critical safety difference, with long life and even wear, I’ll have slotted or drilled rotors on every car.


*Many years ago, as I was driving on I-91 in rain/sleet, in my 1985 Volvo 245 Turbo, I braked for an exit...and ZERO brakes. Despite good pedal pressure, no deceleration whatsoever. The rotors had iced up as they were right below freezing with liquid moisture in the air. I had no brakes. I skipped that exit, drove ten miles to the next one, while pressing the brakes. Several applications later, I had melted the ice film, and had good brakes again. I applied the brakes periodically for the rest of the drive, until the weather had changed completely to snow.
 
I guess I’ll be the iconoclast and say that drilled and/or slotted rotors do work better in some circumstances.

I’ve got drilled rotors on my Mercedes, the 2002 V70XC and the 2001 V70 T5. Better brake cooling under hard use was the intent, but what I notice is quicker bite in the rain and in slushy/snowy conditions where moisture gets on the rotors*. There is a path for the water to be squeezed out. No weird noises. No cracking. Long life. All good.

I’ve got slotted rotors on the 2002 V70 T5. Yep. Weird whoosh noise under heavy braking, but again, in wet, particularly, freezing wet, there is better initial bite. Also, and I didn’t expect this, longer rotor and pad life. I got 100,000 miles out of my first set of front slotted rotors. The slots allow the pads to stay clean, and avoid embedding tiny bit of debris. Very smooth, even wear was the result.

I liked them so much, I bought another set for the car.

For the performance increase in adverse conditions, and the critical safety difference, with long life and even wear, I’ll have slotted or drilled rotors on every car.


*Many years ago, as I was driving on I-91 in rain/sleet, in my 1985 Volvo 245 Turbo, I braked for an exit...and ZERO brakes. Despite good pedal pressure, no deceleration whatsoever. The rotors had iced up as they were right below freezing with liquid moisture in the air. I had no brakes. I skipped that exit, drove ten miles to the next one, while pressing the brakes. Several applications later, I had melted the ice film, and had good brakes again. I applied the brakes periodically for the rest of the drive, until the weather had changed completely to snow.
Thank you.
 
I’d go with regular rotors and the Akebono pads like you mentioned. I feel slotted rotors are mostly for performance cars and stuff like that. I personally have no experience with the slotted rotors so I can’t speak on the noise or anything that the other posters have mentioned about them.
 
I’d go with regular rotors and the Akebono pads like you mentioned. I feel slotted rotors are mostly for performance cars and stuff like that. I personally have no experience with the slotted rotors so I can’t speak on the noise or anything that the other posters have mentioned about them.
Blank/plain rotors are certainly jsut fine but like a lot of things I read on this forum, folks' recommendations are often based on what they've heard vs. folks with direct experience - running slotted and/or drilled on 3 vehicles...nothing odd about them....great braking performance.
 
I just purchased a Powerstop rotor/pad kit for my brothers Tracker and he loves them. I just had my OEM rotors turned and installed standard pads on my 05 GMC Sierra. No drama. My next brake service I will be trying out the Powerstop kit.

My personal opinion on importance of any brake job is to properly bed in the pads/rotors right after the install. I have found it not only helps with modulation but also keeps them quiet.

Of course all bets are off with full sintered pads. I doubt there is anything you could do to make those quiet. My dirt bikes alway squeal with those installed. It's a fair tradeoff for fade free performance.
 
I just purchased a Powerstop rotor/pad kit for my brothers Tracker and he loves them. I just had my OEM rotors turned and installed standard pads on my 05 GMC Sierra. No drama. My next brake service I will be trying out the Powerstop kit.

My personal opinion on importance of any brake job is to properly bed in the pads/rotors right after the install. I have found it not only helps with modulation but also keeps them quiet.

Of course all bets are off with full sintered pads. I doubt there is anything you could do to make those quiet. My dirt bikes alway squeal with those installed. It's a fair tradeoff for fade free performance.
Agreed - I did the Powerstop pad/rotor kit(s) for both vehicles that I run them on off of rockauto - my Atlas was about $210 for the fronts and the Lexus was a full f/r kit for $400. Not a lot to me for something that only gets done once in a blue moon.
 
Something I have noticed over the years is when someone is buying a part based on how it looks its pointless to try and convince them otherwise.
Like they folks who put rear wings and body kits on a Toyota Corolla, the thing looks like a rolling joke but to them its cooler than snake poo in a glass of ice water.
The Power Stop are nothing special but they work.
 
Something I have noticed over the years is when someone is buying a part based on how it looks its pointless to try and convince them otherwise.
Like they folks who put rear wings and body kits on a Toyota Corolla, the thing looks like a rolling joke but to them its cooler than snake poo in a glass of ice water.
The Power Stop are nothing special but they work.
Slotted and/or drilled rotors hardly on the same playing field as a giant wing and fart can muffler on some kid's Honda Civic. The question to ask really is...does the extra money spent on that v. small improvement in braking worth it for a DD? Only the owner can answer that. Do you need this? Of course not and regular/cheap/basic blank rotors work just fine.
 
I use the 240 wagon mostly for long distance, heavily loaded travel. Rocket box, awning, full rear compartment, suitcases and two mountain bikes. On my initial trips out west I would arrive home with the front rotors badly warped. It happened every trip. Ate rotors, PBR Ceramic pads.

I did some research and installed Cquence slotted and drilled rotors and Textar OE formula pads. The rear pads were switched from ceramic to Textar pads but we kept the Ate solid rotors.

After the 7,400 mile trip last summer the rotors were fine. No warping or pulsing. Despite 8 passes over 9’000’ and some long decents. Like the the one into Los Alamos from the Bandolier National Forest where I had to stop to cool the brakes. I measured the rotor temp on the hub at 524 degrees while stopped.

I was told the OE pads absorb heat better than ceramics. And the slotted and drilled rotors stay cooler. I don’t know if this is true but it solved the warping issue. The brake dust is off the charts - the only drawback. Picture taken above Jemez Springs NM.
 

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If you want to be able to machine the rotors if needed later on then do not buy the drilled rotors. If you would only replace them and not consider machining that is a moot point.

I will not buy drilled rotors due to the amount of ones I have seen with heat cracks. It's very possible that these the cheapest of the cheap rotors but seeing that multiple times has made me leery of using them.
 
If you want to be able to machine the rotors if needed later on then do not buy the drilled rotors. If you would only replace them and not consider machining that is a moot point.

I will not buy drilled rotors due to the amount of ones I have seen with heat cracks. It's very possible that these the cheapest of the cheap rotors but seeing that multiple times has made me leery of using them.
That is certainly a downside - hardly anyone even machines them anymore as they are so cheap to replace. I too have heard about heat cracks and this is the first time I've had drilled rotors so will keep an eye on them. These are in two of our around town/daily SUVs, no towing...I'm sure they will be fine. On my car, I did slotted only b/c it will see some track time and regularly is driven in "Mexico"..hahahaa
 
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Something I have noticed over the years is when someone is buying a part based on how it looks its pointless to try and convince them otherwise.
Like they folks who put rear wings and body kits on a Toyota Corolla, the thing looks like a rolling joke but to them its cooler than snake poo in a glass of ice water.
The Power Stop are nothing special but they work.
I’m confused, I had no initial intention of going drilled slotted, the main driver was that the cost of the axle kit in question is cheaper than a ceramic Akebono pad with a decent quality rotor. With my occasional towing I wondered if the performance of a rotor of this type would be beneficial over a more known quantity in the ProAct ceramics. While I see some aesthetic appeal, let’s be honest I’m putting this on a D40 Nissan Frontier, hardly the coolest, most performance oriented, or most aesthetically pleasing vehicle on the road. Regardless I ordered the Raybestos Element 3 pads and raybestos blank rotors from rock auto based on the recommendations I received and will report on their performance.
 
The problem with drilled rotors is that they can crack and break, which is not an enjoyable experience.
 
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I’m confused, I had no initial intention of going drilled slotted, the main driver was that the cost of the axle kit in question is cheaper than a ceramic Akebono pad with a decent quality rotor. With my occasional towing I wondered if the performance of a rotor of this type would be beneficial over a more known quantity in the ProAct ceramics. While I see some aesthetic appeal, let’s be honest I’m putting this on a D40 Nissan Frontier, hardly the coolest, most performance oriented, or most aesthetically pleasing vehicle on the road. Regardless I ordered the Raybestos Element 3 pads and raybestos blank rotors from rock auto based on the recommendations I received and will report on their performance.

Elements 3 are very good for a fair price. Highly recommended.
 
The problem with drilled rotors is that they can crack and break, which is not an enjoyable experience.
I’ve heard that, too.

But I’ve yet to experience it.

With over 100,000 miles on drilled rotors on the Mercedes and over 50,000 on the wife’s XC, not even a hint of cracking.

Perhaps cracking is associated with drilled rotors because they used to be on very high performance cars, cars that experienced extremely high brake rotor temps?
 
From my personal experience with them I would say you will be very pleased with those Raybestos Element pads.
 
I’ve heard that, too.

But I’ve yet to experience it.

With over 100,000 miles on drilled rotors on the Mercedes and over 50,000 on the wife’s XC, not even a hint of cracking.

Perhaps cracking is associated with drilled rotors because they used to be on very high performance cars, cars that experienced extremely high brake rotor temps?

This is what Zimmermann say about it.

7. Crack formation

Fundamentally, Zimmermann brake discs (standard and perforated design) are manufactured according to the respective original replacement part regarding the dimensions and the material used (GFO-ISO9001-TS16949).
Perforated designs were tested for functionality, reliability and wear resistance by TÜV Nord and approved by the Federal Motor Transport Authority for the intended use in production vehicles. The brake discs meet the requirements, which are encountered during routine operation with respect to mechanical and thermal stress.
During the operation of brake discs in modified vehicles, during rally/race driving and/or with an aggressive driving style, the requirements are of course much more demanding in terms of the mechanical and thermal loads placed on the brake discs. This also applies when using race pads.
The formation of net-like or radially extending cracks on perforated brake discs is normal. According to the directive “Requirements for the testing of replacement and special brake discs and drums for vehicles" from the TÜV NORD, these are permitted up to the following values:
  • Max. length: 0.5 x brake disc width
  • Max. width: 0.2 mm
  • Max. depth: 0.2 mm
If these limits are not exceeded, there is no damage according to the statements of the aforementioned Directive. Larger sized cracks solely occur through mechanical and/or thermal overstress. Reasons for this may include:

 
So, if you go to your average track you will see on normal cars bunch of oldtimers running good, proven regular rotors. They run really, really good pads and brake fluid. That is what matters if you have proven rotor.
When it comes to drilled rotors, be careful which brand you getting. Slotted too, but there is more room for flexibility as rotor is not obviously drilled.
Drilled and slotted rotors? I put them in category of cold intake air systems. It is absolute waste of money, except it can cost you life.
I would go regular rotor, but if you expecting more work on brakes get Hawk LTS or EBC Greenstuff. Apparently Stoptech Sport pads are really good bang for a buck, but no personal experience yet. I will try them though.
 
... Looks like my 2017 Nissan Frontier is due for its first Pad/rotor change (actually rotors look good but I usually do it all in one shot) I went to look at ordering pads and rotors and stumbled upon these on tire rack of all places.
...
If it ain't broke, don't fix it.
If the rotors look good - smooth, even wear pattern, thick enough, not warped - why replace them? IME, under normal use, rotors last much longer than pads.
 
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