robsjeep

What upside and downside if any are there to drilled and slotted brake rotors verses plain rotor? Specifically looking at my front brakes. I got big tires 33x12.5 My plain rotors and pads need replacement, and I see RockAuto has drilled and slotted rotors made by Dynamic Friction, for $43, verses about $20 for the plain rotors.

Are drilled and slotted good? Any downsides if used off roading, i.e. do they tend to pack with dirt, cause issues?

I know little of disc brakes, old drum guy here. Thanks!

4.3L XJ

I have them on my Crown Victoria with ceramic pads. Stops much better than before. No down side yet unless it is faster rotor wear

jpz

I have slotted rotors on my Mustang. I have read that rotors with drilled holes, not cast holes are prone to cracking. I can't say from experience if this is true, but I can tell you that my slotted rotors have held up fine for years now with no noticeable wear on the rotors or the brake pads.

BlueRidgeMark

Hmmm. That's an interesting point. I have no idea, since I don't do any real off-roading, but I think that's one base you sure want to cover before you make a purchase.

The main purpose of drilling & slotting is better cooling. So, if you drive fast and corner hard a lot, or if you do long downhill stretches where you need to break a lot, they are the ticket.

It does cause faster pad wear.

tech

I have drilled and slotted on all my cars and my Cherokee I like them off road because if they get dirt or mud and water on them it gives the mud ,dirt or water a place to go and they will stop better and dry out faster . the surface of the rotor cleans it self off much faster and the other thing is it takes a lot to warp them .

fb97xj1

https://www.brembo.com/en/company/ne...led-or-slotted

robsjeep

That is good info!

One concern I hear is cracking in drilled rotors, but it may be atribuated to poorly made cheapo drilled rotors, not correctly drilled quality rotors.
So what brand(s) drilled rotors have you been satisfied with?

tech

I work on Police cars and they have drilled and slotted and they do crack but the cracks are really small but Police cars get the rotors red hot at times and it does take more then one time getting them red hot to start to crack and the cracks are not going to make them brake apart because we never had one brake apart

robsjeep

error post

vroomvroom

Drilled and slotted or even two-piece rotors make sense on a high performance car where there are situations that warrant high speed braking like on a track with tight turns or a straight away that leads into a sharp corner. You won't see a difference in a vehicle like the XJ except for a lighter wallet. The brakes suck on an XJ. They will continue to suck short of a big brake kit or a caliper upgrade (something like the WJ upgrade)

Corky

Tracked vehicles don't have a mud pit to clog up the slots/holes on the rotor.. Guess what happens when the pads can't wipe the rotors when offroading... I've had just the opposite experience with mud clogging up the holes and slots..If anything they added more yards to the stop when loaded up...Maybe I bought the wrong style ??

woodbugger21

I have them on my 96 XJ, do they work fine, yes, was it worth it and necessary, absolutely not haha. I did it because I could I guess

IJM

The best thing you can do for on-road braking performance on a Cherokee is get some front pads with good bite and fade resistance. It'll made a big difference compared to screwing around with drilled and/or slotted rotors. I use Hawk LTS, but there are other options out there. So much better than the crap you get from Auto Zone or wherever.

lawsoncl

Definitely, upgraded ceramic pads make a huge difference.

4.3L XJ

I agree with that