I have always liked the look of a cross drilled brake rotor. I have done it several times to VW Sandrail Dune buggies that never see the street.

There are several companies that offer this and have the usual hype about how great theres are.

I have read that it is mainly a cosmetic thing nowdays because we have better brake material. I also read that it can cause stress riseser and premature rotor cracking which our L has had problems with all along. Not to mention that agrivating brake dust that is always on my rims.

None the less I would like to find out more about it. I think it would look great on our four wheel disc trucks.

Here is just one example but they don't list our trucks.
http://www.secureleadercom.com/asp/d...sp?goto=frames
Anyone have comments or a link that includes our L?
Anyone seen one done?
I have seen some grooved ones that look nice also?

 

My Brembos have not cracked. And I have worn them down to the point that the holes no longer have a chamfer and taken them road racing several times. So if they were going to crack, they probably would have.

But the Brembo rotors that come with the Gran Turismo kit are cast with cross-drilling in mind. That's a totally different situation thna just drilling a stock rotor, which will probably crack.

I know that Brembo offers replacement rotors for the L (2WD F150), but I don't know if their replacement rotors are cast with provisions for cross-drilling or not. I'd check with them.

I have matching Powerslot cross-drilled rotors on the rear. They have not cracked, but that really says little about whether drilled Powerslot fronts would crack.

 

Raybestos makes them and sells them through your local Mieneke shop. Slotted and cross drilled with slanted venting. I haven't tried them myself; but, that's an option.

 

http://www.raybestos.com/usa/rotors.htm

 

Stan sells them. RUSLOW

http://ruslow.com/Brakes.html

 

If you are really just going for aesthetics on this, then I would stick with slotted or dimpled rotors. Drilling does two things, one as you mention

1) Creates stress concentrations. Even if they are chamfered, a hole is still a stress concentrator by itself. The stresses that will actually cause the cracking are thermally induced. That is, if you never really get the rotors hot, they probably won't crack.

2) Holes remove material, reducing the heat capacity of the rotor. If you make a 60-0 stop, you are putting X amount of energy(heat) into the rotor. If you drill it, it will have less material to absorb that heat, so the rotor will get hotter than an undrilled rotor. It might cool faster with the drilling(debatable), but it will initially get hotter.

I have 14" x 1.4" discks on my L. They are huge, they are drilled and they have not cracked(like Tim's above). But when I replace them, it won't be with drilled rotors, only slotted, mostly for reason #2.

Randy

 

As allways, Thanks for the input and links etc.
Nothing like first hand experiance to shed light.
Looks like I get to spend some more time reading about my favorite ride.

I shouldn't be spending so much time here. I swore when I bought this truck that it was perfect and didn't need anything.

But seeing and hearing of everyone's mods is very inviting.
Maybe I will work on my taxes a little to hehehe

 

EZGZ:
From what I've heard, cross drilled is better to go with than slotted for street driving. According to the Brembo rep I talked to, cross drilling helps get rid of dirt and everything that may build up while driving.

The cross drilled cool about 150degrees over smooth rotors, where slotted cool 40degrees. Also the cross drilled perform "light scrubbing" of the pads, and as I said the dirt, water, and debris goes right through the holes so the pad has more rotor contact.

In slotted, there is hard scrubbing, but the dirt and debris clogs up. If you use the cross drilled on the track, they cool way too quickly and the heat can cause cracks while eating the pads up.

But yes, the Brembo cross drilled rotors are made with the holes precast (I believe). If you see rotors that say "Brembo cross drilled/slotted", stay away from those as those are bought as Brembo smooth rotors, and are cross drilled and slotted afterwards, compromising the integrity.

Email me if you have any other questions. Also, if decide on Brembo, theres a GP going on right now (check the GP forum).

Gagan

 

Ok so let me get this strait....
The cross drilled "perform a lite scrubbing on the street" but they "eat up the pads on the track".



http://stoptech.com/faq/data/faq15.html

Stoptech has much good info on their site. I really like the page about rotor warping myths.

http://www.stoptech.com/whitepapers/...otors_myth.htm

Jerry

 

OMG
A Brembo rep told you this? Whether it's a Brembo rep or a Ford dealer trying to sell you Mercon V, it's all the same.........

Randy

 

I should have put a disclaimer in there, hehe. What I meant was eat the life of the pads.

As for the rotors, the reason they are worse for track is because while at the track (especially AutoX or road course... anywhere where the brakes are used a lot), on a stretch where you wont use the brakes the rotors can cool, you use them again they start to heat, causing the big gaps in heat-cool cycles. I think thats what he meant anyway.
Also Stoptech's links are very good and I may eventually end up getting their brakes too (from what I've heard they're better than Brembos in caliper stiffness). However the second link you listed doesnt show much about drilled and slotted rotors. Just cracking

desert: True enough and I see your point.

Gagan

 

I got some drilled and slotted rotors off of ebay awhile ago. Not some cheap like 30 buck rotors, they were over 300 bucks. Anodized or something like that. Can't remember who makes them, no one I had heard of.

I have not had any cracking issues after about 6 months, and dust is less on the front the wheels. I did switch to Napa's ceramic brakes (I recommend. Came with new shims, lubricant, and stop very nicely!) but have had no problem. I would just suggest a good quality rotor. You know you will always have abunch differing opinions from the people who sell rotors. I can say I drive just on the street, short and long drives the rotors have put up quite nicely (and look good as hell as well).

Performance: Unsure, it took awhile to get everything on and brakes bleed perfectly. I didn't try and brake fade tests, it seemed better, but what the hell do I know? The rotor is bigger, it's slotted, and drilled. So logically the biiger rotor, and slots and drills should help. I guess. No complaints.

I mainly did it cause my current rotors were warped. Actually, what the hell do I know? I don't test it or anything, I drive and it's fine.

 

EBC makes a nice slotted and dimpled cost effective replacement for the L's

 

Tire rack carries both EBC and Power Slot.

http://www.tirerack.com/brakes/resul...perf&x=85&y=12

 

Stillen

http://www.fordtruckpower.com/custom...7bee43a87389ff