Your memory is not bad.

Holes in rotors were for autocross to reduce weight. If they are cast in holes like OE does, they have a chamfer on both the rubbing and vented side to reduce the cracking tendency. Slot can have some effect with a brake material that is operating in a higher temperature range then it was designed for, but the friction material has to be stiff to beige the gap and not have excessive wear. But a diff pad is more prone to heat banding. Both of these situations might have less mass than what the OE design has, and mass is good.

Disc-Disc vehicles run so much cooler that what the disc-drum vehicles used to. Unfortunately, that allows mostly in the aftermarket for companies not not cure the pads as much as they should, or not have a high temp material. Both reduce cost.

Since I got into brake testing years ago, recording brake performance and fade resistance, I've never bought rotors with hole or slots, except for motorcycles were those were the stock rotors.

 

Now you all have me thinking! So, slotted and crossdrilled with carbon fiber ceramic pads arent preferred for towing? I was always under the assumption they were!!?? What is preferred then?

I talked to Powerstop this morning, they are shipping me a new set of hubs/rotors. Hopefully get them early next week, ill be a master doing these things in no time. Sucks I have to buy new bearings and seals again though, all that money was wasted! Another set of Timkins on the way! Less than 100 miles on new ones, could i reuse them?

 

The biggest issue is going to be mass. Sometimes, slots can be effective if the friction material is outgassing. But that would be due to a friction material not being cured enough for the situation or the organic materials having too low of a temperature range.

Many people run slots and holes without any issues. Is it the best situation? That depends on the situation. The biggest problem I have with aftermarket rotors is that they rarely meet the surface finish and installed runout required by the OE manufacturer.

The slots and holes are appropriate if your vehicle operation leads to smoke and odor from the friction material. But again, proper friction material for the application would not do that.

The runout issue leads to pulsation, and the aftermarket paired solution uses an abrasive friction material, so the rotors wear into a lower runout.

Ceramic pads are reinforced with Potassium Titanate fiber. Some companies call it carbon fiber, but those are two different things. We would often product test our competitors and do chemical and physical analyses to get a handle on their formulations. In the aftermarket, sometimes there would be a smidgen of a product in a formulation, so marketing could say it's in the formulation. During my last years, we merged with that company. The aftermarket terming and marketing is the Wild West.

I doubt you will have any major issues, but it's not what I would spend money on. You might feel they stop better, but that would be due to the change in friction material coefficient, not the rotors. On this truck, I always use OE rotors.

The bearings can be used again. Used bearings of any miles can be used as long as they don't exhibit scoring issues, excessive heat, or other damage. The seals I would replace due to the potential of distortion.

 

Like I have said in the past, the best last pads I got my hands on with the Ford HD Blue pads.
Can you get that pad any more I can't say? They stop well and don't dust up and seem to last.
As for towing, I can't say. They were paired up with new stock rotors.