Slotted rotors off road

The internet is littered with forums where this exact question is asked. Almost every response to the question is flaming OP for asking such a stupid question. I have yet to find anyone who has any real experience.

I couldn't care less about the slot for gas ejection, what I find interesting is the possibility of the rotor scraping the pad.

Does anyone have first hand experience with this?

 

I ran slotted rotors on my Solo II car. They did provide 'some' improvement during wet braking

But I don't really know what you mean by "the possibility of the rotor scraping the pad".

I mean the rotor is still a flat surface that the pad grips when hydraulic pressure is applied.

 

With a properly designed slot and correct pads, you won’t need to worry about pad “damage”.

 

I've been running StopTech 4Runner slotted rotors with Advics OEM-equivalent ceramic pads since 2021. The slots do help scrape away contaminants and water from the pad surface in my experience, so the brakes are effective sooner after driving out of a mud hole or water crossing:

 

I've actually dealt with this before. From what I experienced, the rotor scraping the pad isn’t something that usually happens if everything’s installed correctly and you're using the right components. Most issues arise from improper installation or worn-out parts. If you’re noticing scraping, it’s worth checking your setup and possibly replacing the pads or rotors.

 

Z36 package?

 

What do you mean by improper installation?

 

My experience is from having worked in an automotive upgrade shop, doing brakes, exhausts, intakes, etc.
Slotted rotors talk about out gassing, but today's pads don't do that.
Slots aren't going to "wipe away" contaminates like some kind of cheese grater.
They can add a very small amount of surface area, but also introduce a place for heat cracking, because it's an edge right where heat is being disipated.
That being said, I have Stop Tech slots on the wife's HRV and it stop phenomenally well...but I think it's more due to pads.
The Tacoma and Ridge line are both just plain rotors with good pads, and they both stop very well.
Just buy some good rotors, but pads is where the magic happens.

 

My brain is saying that slots would make negligible difference off road or even be a slight disadvantage. The slots would not act as extra squeegees against the pad, or at least any better of a squeegee than the front of the pad face itself. The best way to dry a rotor is to heat it. And for slow speed applications where you aren't needing to shed F1 levels of heat, the more surface area you have, the better.

 

As Lance said, the proper pads are the key. On my one car years ago I upgraded to a much bigger rotor set up (stock fit under 15" wheels, New set up required 17") and with just a set of Raybestos pads there wasn't much of an improvement. Then I went to a set of Hawks that were borderline track pads and once they got a little heat in them holy crap did they bite into that rotor.