That was one of the reasons that the '99-04 trucks had rotors from TRW that were post vane. '05 and above TRW went back to less expensive straight vane rotors, there is more flexure between the vanes during hard braking. But there can also be casting issues and pads where the compliancy is too stiff. Vanes and stiff pads were the reason the OBS used to crack rotors, with the high bias of the front brakes, disc/drum.

 

Just a comment here. As I used to take new hires and spend a few days “training” them driving the big rigs.

”If you drive this thing like it has no brakes you will generally have brakes when you really NEED them”!!

And now you’uns can go on your merry way! Kudos t@Too Many Toys for his information

 

If those pistons started to jam you could easily have hot temps on that side of the rotor. In my world, rotors are four sections, the hat or carrier, the vanes, and two rubbing discs. One disc can get pretty hot, and in normal operation, the inner disc usually runs hotter. You have to get to about 800ºF with most OE friction material to get the ammonia and formaldehyde from the phenolic resign friction material binder to outgas in a high enough amount to smell it in the cab or by the wheel. But sustained higher temps in the 300-400ºF range can heat age the boots, and once they lose their integrity, the piston sticking just gets worse. But post FUBAR issue, the boot/piston that came first is impossible to tell.

Slide pin hangup tends to cause outer pad issues since the square o-ring seals pull the pistons back away from the rotor, which gives the inner pads clearance. Those o-ring also heat age and lose their ability to pull back the pistons over time. It's generally considered that when you change pads without changing calipers that you will only get 75-80 of the life out of the replacement set of pads due to the pad contact against the rotor, which then leads to more probability of brake pulsating from Disc Thickness Variation. When I do oil changes and under the vehicle, I usually bring a wrench with me so I can back off the caliper pin bolts about 3/16 to 1/4", then I can check for side to side movement of the pins so I know if they are starting to drag from rust.

 

Thanks. Its funny you said that. When I take my grandchildren out for my version of defensive driver training, when we are on a long deserted road I say to them, now stop the vehicle without using the brake pedal. Then we turn around and I show them how long it took to do that. It gives a new appreciation of brakes. With my first car, a '66 Mustang with drums all around, I experienced brake fade with 5 passengers in the four-passenger vehicle. Blew right through that stop sign late at night. I put the best shoes in that car after that. A good lesson at the age of 17.

Testing tractor-trailers, I used to leave my test drivers at home and do it myself, or at least push them out of the way for part of the test.

 

I think I've flushed the fluid in my 13 three, possibly four times in 95K and each time the fluid has come out looking like it needed to be flushed. Having the pressure bleeder makes that job super easy, just have to flush once, take a drive on a dirt or gravel road and activate the ABS a few times then another quick flush.

The calipers, rotors, flex lines and pads were all replaced around 88K. Slide pins get lubed every 20-30K.

These trucks do take a lot of attention to the brakes compared to the previous GM trucks I've owned. My prior 06 2500HD needed slide pin and bushing maintenance maybe once in the same time period, and that's because the bushings got to where the calipers started rattling. GM was famous for using ceramic pads which didn't wear out nearly as fast as the semi-metallic pads Ford uses.

 

I last did brakes on my Excursion about 20,000 miles ago. I'm about ready to take a trip with the RV, maybe I'll go out and pull all the calipers today and inspect before I leave. And lube the slide pins while I'm at it!

Edit: I'm very glad I did. One slide pin on the right side was stuck, and one on the left side is seized so bad I can't get the pin out. Headed to Napa for a replacement.