Drilled, Slotted or Both?

[grady]

This isn't about my TVR but is about the old family (kids, wife, dog and clutter) hauler, a SUV that seats 8 comfortably and yet has 12 cup holders, fondly known as a "Texas Cadillac". I had to grin reading through the service file, the sales brochure described it as: "Like A Rock"... obviously before the price of fuel went up.

It's a heavy vehicle with rear drum brakes so the front brakes take a lot of the load.

The question is about the front disk brakes... The OEM rotors lasted about 30,000 miles before warping. I replaced them with high quality slotted aftermarket rotors. 100,000+ miles later I need to replace them again.

But now I have the choice of slotted (in different flavors), drilled or both. Looking around drilled rotors seem to be widely used by Mercedes and others. Yet some threads on PH suggest they will lead to failure. Exploding star cruisers come to mind.

What is the collective minds' best thinking on my choices (and giving up the vehicle to save the planet isn't a current option). Thanks Grady

[rev-erend]

Slotted are always best IMHO.

Drilled are really just for posers and for show. They will get cracks eventually.. so unless you are posing in this vehicle (could you) then slotted is the way to go IMHO.

[wedg1e]

rev-erend said:

Drilled are really just for posers and for show.

That'll be why bikes have them then

No chance of them cracking on the ST13, they wear out too quickly for that

[350zwelgje]

Slotted only. Drilled only in very good quality discs, not the cheap ones, as Alan said they will develop cracks.

Rob

[GreenV8S]

Do you *need* slotted or drilled discs? They only reason you're likely to need them is either that you're getting the pads so hot that they're starting to gas, or you've got extremely hard pads in and need the cheese grater effect to stop them glazing over. Neither of these seem likely if you have production pads driven sensibly on the road and manage to stretch them out to 100,000 miles. If you don't need them, then grooves and holes are just decreasing the pad bearing surface and increasing noise and pad wear. If you decide that you definitely need them then go for grooved rather than drilled. Drilled discs are just bad, m'kay?

[Boosted LS1]

Oops I thought this was an SAS thread. They drill and slot.

Boosted.

[honourablepickle]

soft pads - plain discs
hard pads - grooved discs
too much cash - alloy bells ,quality drilled rotors

hp

[grady]

Thanks all, slotted it be.

There is too much hot and heavy braking (I forgot to mention trailer towing too) so go with OEM quality.

It just that are more options on the market than last time around. Grady