Hey all,

I just want to discuss the different types of disc brakes. This is more of a quick summary...it is not a technical disection.

Basics:

Disc brakes = good.

Vented disc brakes = better because better cooling/less fading without decreasing stopping distance.

Cross-drilled vented disc brakes = great for cooling (less fade), but cross drilling can lead to increase brake pad wear, cracking of the disc itself (strength compromise), and less brake pad to disc friction (because of the holes). So, cross-drilling alone may INCREASE braking distance and decrease durability on both disc & pad.

SLOTTED vented disc = best compromise between plain disc and cross-drilling. Since it is slotted, rather than having holes, then strength is still good. Brake pad wear will be increased but not as bad as cross-drilling. Stopping distance will be just as good (or almost) as plain vented disc. But, cooling will be better than plain disc.

Basically, if you were just driving your 4runner on the street, then vented disc brakes are all you need.

The ONLY time you would need slotted disc brakes or cross-drilling is if you do track racing where repeated stops need a lot of cooling of the discs.

However, many people also upgrade their discs just for looks.

Hope this helps.

I love my slotted rotors. I am hard on brakes and they have yet to let me down. One thing about them is that you have to convert to carbon metallic brake pads which are harder and you also get this grinding feel with the brakes, but its not bad. Another downfall to slotted rotors is that you can't turn them. If they get warped, they are toast and you ahve to buy new ones. Another up side to the slots is that they are an easy way to test the thickness of the disk. Once the slots are gone, its time for new pads!
A thing about cross-drilled. There are two types of cross drilled. There are the real kind and the fake kind. The fake kind are regular disks that have holes drilled into them. I would not recomend these at all, they are the ones that are giving cross drilled rotors a bad name. I don't think they make any real cross drilled rotors for the 4Runner unless you get a full on big brake kit. Thats when you get into the real cross drilled rotors. These rotors are formed with the holes in them and are significantly stronger than the other. Your brakes are one of the most important systems on your rig, it was the first mod I did. Imho, you can't have too much brake power.

just my .02

Turboale,

How's the noise level on those carbon brake pads?? I have heard that they make quite a screeching noise.

Well, thats a funny thing. They squeeeel right now, but they seem to have moods. Some times they will be really bad, and others dead quiet. I think its sand/dirt getting on the pads from 4x4ing. :dunno: Since I don't have any skid plates in right now, I should behave enough to clean them out and I'll let you know if they get better.

This information is from Luke at Tire Rack. I got this off of altimas.net (where I normally reside).

Slotted or drilled ????
slotted rotors maintain approx. 96% of the friction surface
drilled rotors maintain approx. 85-93% of the friction surface
drilled and slotted only maintain 80-91% of the friction surface

For many years most racing rotors were drilled. There were two reasons - the holes gave the "fireband" boundary layer of gasses and particulate matter someplace to go and the edges of the holes gave the pad a better "bite".

Unfortunately the drilled holes also reduced the thermal capacity of the discs and served as very effective "stress raisers" significantly decreasing disc life. Improvements in friction materials have pretty much made the drilled rotor a thing of the past in racing. Most racing rotors currently feature a series of tangential slots or channels that serve the same purpose without the attendant disadvantages.

the process of drilling rotors and slotting rotors was done for 1 reason and 1 reason only it is to disipate the gases that build up between the pad and the rotor which occurs under extreme heat ( when braking very aggressively like on a road course) and it has absolutely nothing to do with heat disipation. the only way to transfer more heat away is by using a larger heat sink which means use of a larger rotor whether in diameter or thickness. Since the caliper will only allow for a certain rotor thickness that solution is not very applicable because, if you are changing tha caliper opening width you might as well get a larger rotor diameter at that time

1) The brakes don't stop the vehicle - the tires do. The brakes slow the rotation of the wheels and tires. This means that braking distance measured on a single stop from a highway legal speed or higher is almost totally dependent upon the stopping ability of the tires in use - which, in the case of aftermarket advertising, may or may not be the ones originally fitted to the car by the OE manufacturer.

2) The brakes function by converting the kinetic energy of the car into thermal energy during deceleration - producing heat, lots of heat - which must then be transferred into the surroundings and into the air stream.

The amount of heat produced in context with a brake system needs to be considered with reference to time meaning rate of work done or power. Looking at only one side of a front brake assembly, the rate of work done by stopping a 3500-pound car traveling at 100 Mph in eight seconds is 30,600 calories/sec or 437,100 BTU/hr or is equivalent to 128 kW or 172 Hp. The disc dissipates approximately 80% of this energy. The ratio of heat transfer among the three mechanisms is dependent on the operating temperature of the system. The primary difference being the increasing contribution of radiation as the temperature of the disc rises. The contribution of the conductive mechanism is also dependent on the mass of the disc and the attachment designs, with disc used for racecars being typically lower in mass and fixed by mechanism that are restrictive to conduction. At 1000oF the ratios on a racing 2-piece annular disc design are 10% conductive, 45% convective, 45% radiation. Similarly on a high performance street one-piece design, the ratios are 25% conductive, 25% convective, 50% radiation.

3) Repeated hard stops require both effective heat transfer and adequate thermal storage capacity within the disc. The more disc surface area per unit mass and the greater and more efficient the mass flow of air over and through the disc, the faster the heat will be dissipated and the more efficient the entire system will be. At the same time, the brake discs must have enough thermal storage capacity to prevent distortion and/or cracking from thermal stress until the heat can be dissipated. This is not particularly important in a single stop but it is crucial in the case of repeated stops from high speed - whether racing, touring or towing.

4) Control and balance are at least as important as ultimate stopping power. The objective of the braking system is to utilize the tractive capacity of all of the tires to the maximum practical extent without locking a tire. In order to achieve this, the braking force between the front and rear tires must be nearly optimally proportioned even with ABS equipped vehicles. At the same time, the required pedal pressure, pedal travel and pedal firmness must allow efficient modulation by the driver.

5) Braking performance is about more than just brakes. In order for even the best braking systems to function effectively, tires, suspension and driving techniques must be optimized.

haha,
I like the
"brakes don't stop cars, tires do" the little, sales pitch thrown in with some good information. Not saying its not true, tires are something I'll never slouch on and why i'm not running MTs right now... but thats besides the point.

but to sum that all up heat = the devil, the bigger the better, slotted is the way to go unless your going to spend $$$

Any updates on best disc brakes? What are you guys using for 1) great braking power and 2) reliability/endurance? I live in Colorado, and travel to the mountains often. I want to have maximum brake authority, and I need them to last. What have you guys found to be great solutions? I have Akebono "Ultra premium ceramic brake pads" ready to install with new discs.

Was there ever an answer to this...I'm in need of replacing my OEM setup at just over 80k miles...it's been lifted, armored, tires, Et al since 22k miles...the brakes are just starting to feeling spongy. Any best suggestions?!

-Ryan

I've EBS slotted and dimpled front rotors and even with generic CarQuest brake pads these are far superior to OEM setup.

I'm weighing an upgrade to the Powerbrake Stage 1. The rig has gotten heavy and these can do the job. They are a beautiful work of art, which helps the sale. Earlier comments regarding the wheels doing the actual stopping are relevant - I could have the most effective brakes anywhere, but if the tires don't provide the traction I'll just have the ABS cycling during a hard stop.

I'm weighing in with my OPINION which is likely DIFFERENT than most.
Bear in mind my opinion is worth, to you, exactly what you paid me for it.
(So please don't shoot me just because I have a KISS philosophy on things.)
(Also please don't shoot me for not believing in highly marketed products.)

I use the basic stuff.
If you believe in the fancy stuff then that's fine for you.
If you want to chastise me for using basic stuff, you'd need a good factual reason though - as all my decisions are based on nothing but basic facts.

1. Tires DO stop cars in that the tire friction footprint is all you've got
2. Disk brakes stop the wheels where an E rating is steel on steel (yeah, rotors are usually "gray iron")
3. IMHO, pads are pads are pads (where there are differences but you can't tell ahead of time)
4. Whether a pad is ceramic or semi-metallic or NAO is more marketing than chemistry (IMHO)
5. Certainly some dust more than others & some squeal more than others & some wear faster than others
6. But you can't tell that just from what is written on the pads
7. Besides, it's my opinion you almost can't get a bad pad if you follow logic
8. The only thing you can tell for sure is the cold/hot friction rating of the pads
9. Lots of brake pads have E friction ratings but most are F or G & even H rated
10. Every pad has the cold/hot friction rating stamped on the product (by USA law)
11. So I buy pads by their friction ratings and not much else (shoot me for being factual)
12. Likewise, I feel tires are tires are tires (you have to try to find a bad tire IMHO)
13. So I buy tires by size, load range, and then by the UTQG specifications
14. I have them shipped to my home so that I can mount & balance them myself
15. Similarly rotors are rotors are rotors (as long as they're the right size & spec)
16. Drilled & slotted is more marketing than anything else (IMHO)
17. So my recommendations are simple and easy (YMMV)
18. Plain rotors, pads of at least the same friction as OEM, and tires of about 500AA UTQG
19. Yes, I'm well aware that most of you don't believe in the government UTQG process
20. Yes I'm well aware most of you believe in highly marketed products being better
21. Yes, I'm well aware most of you believe the more you pay the better the product, etc.
22. But in the next breath you will likely tell me you believe in anonymous random online reviews
23. Which makes no sense in terms of logic
24. My logic is simply that I buy by the specs that matter which I can trust to be accurate (anything else is marketing)

Here's what I do when buying new pads/rotors/tires (YMMV).

• I buy the cheapest tires with the best specs (size, load, traction/treadwear/temperature)
• I buy the cheapest pads with the best specs (OEM or better cold/hot friction coefficients)
• I buy the cheapest rotors that fit (don't even get me started on what people call "warp")
• I bed new pads the multi-60-to-10mph way everyone else does (usually at 3am when the highway is clear)
• But more important than bedding is I always keep pad deposition in mind when I'm stopping at a light or intersection!
• Pad deposition starts with a single hard stop-&-hold which, over time, builds up, which can form shuddering at speed

Keep in mind the following (as always, YMMV)

• I replace the tires only when they're almost gone
• I mount and static balance my tires at home (dynamic checks are free or $5)
• I usually replace the valves (I like the chromed brass threaded valves the best)
• Where old tire disposal at Costco is only about a dollar a tire
• I replace rotors only when they are below thickness spec (two or three sets of pads)
• I check my rotors with a mic for thickness (I don't guess!)
• I check runout with a dial gauge and mount (runout is not warp!)
• I replace the pads only when they're almost gone (usually less than 1mm)
• I make my own brake fluid and penetrating oils (I keep them in a Sure Shot steel can)

My simple formula for penetrating oil is 50:50 cheap ATF & acetone.
My simple formula for brake cleaning fluid is 50:50 tetrachloroethylene (aka perchloroethylene) & acetone
(I love acetone! But keep it away from plastic & rubber! Use any ~90% alcohol instead of acetone for plastics & rubber.)

I don't believe in marketing.
Marketing is usually not even true but even when it is true, they don't tell you the cons.
Marketing only tells you the pros.
Almost every pro has an attached con.

Did I mention that I don't believe in marketing?
I only believe in facts.
And I only believe in facts that I know for sure about any product.
Usually those facts are required by law and they're also printed on the product itself.

Rubber is rubber is rubber (within the limits of normal driving of course).
I don't buy anything but an A rated tire where I feel the facts show all A rated tires are "about the same" in friction in normal use.
A bare tire has better friction than a treaded tire (unless it's wet and then a groove is a groove is a groove) IMHO.

Cast iron is cast iron is cast iron (in terms of rotor materials, which is often "gray iron").
All rotors we'll be dealing with will have essentially the same friction coefficient (about E).
All rotors that are of the OEM design (vanes, dual discs, etc.) will dissipate heat about the same.
A drilled and/or slotted rotor is slightly less metal (more surface area perhaps and allows outgassing) but overall, less metal heats up faster (and can crack at weak spots).
(Remember, all highly marketed pros also have cons that they don't tell you about.)

Pads are pads are pads.
Yeah, they have non-asbestos organic pads, semi-metallic pads, and ceramic pads (all very highly marketed products).
All they need is a single spec of clay and they can market the pad as "ceramic" (likewise with a single spec of copper for "semi-metallic" pads).
The pad isn't all that much better than steel on steel so they really don't matter all that much anyway (yes, I know most people won't believe that).
People don't believe steel on steel is an "E" rated friction coefficient for brake pads so take a look at this chart before you say otherwise.

You want to know what I think about gasoline or motor oils or brake fluids or coolants, etc?

In summary, a tire is a tire is a tire, a rotor is a rotor is a rotor, and a pad is a pad is a pad.
I buy the cheapest tire that meets or exceeds OEM specs, the cheapest rotor that meets or exceeds OEM specs, and the cheapest pad that meets or exceeds OEM specs.
YMMV

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Alright, do you happen to recall what they might cost for their stage 1 kit? I don't mind the OE calipers, although, they are the OE 4th gen calipers and not the "updated" 5th gen versions...I need good rotors and great pads understanding that great and pads go hand-in-hand to replacing more often...Powerslot rotors might be my go and than consider the EBC Orange-stuff pads...I wish I would've been on my game more and did the consideration prior to needing sale events that just passed...

About $2500 plus installation.

Thanks for the pricing...I ended spending about $400 for new rotors and pads and SS lines for the front...I was looking at the DBA rotors and yes, they seem to be one of the best options out there but there was a disconnect on what they called rear /front and what I was paying for...I chose the simpleton method and ended up just grabbing some EBC slotted rotors and EBC pads...for having 83k on the 4runner and still on the OE setup, I think that was pretty good as most of it's life it's been lifted and weighted with armor...these new brakes should do what I'm hoping for...less squishy pedal...also, new fluid throughout...