Rear pads/calipers have always been prone to seizing (especially if you live in the salty north), but I would still like to see pictures of said Cheeto pads. I assume he means the pads are rust jacked, meaning rust has caused the friction material to delaminate. The real question is, how much blue rainbow is there on the rotors? If they were overheated that badly, I would expect there to be some sign on the rotor. If the rubber on the calipers is all in good shape, no leaks, and the pins are free... I wouldn't be jumping on the REPLACE EVERYTING wagon so quick.

Unless they are rusted to hell with seized pins, more often than not a quick trip to the media blaster will clean up the caliper bracket and get you back on the road(along with new pads and a brake fluid flush). If you absolutely must replace them with aftermarket just avoid parts store crap, get powerstop or equivalent. $6000 for rear brakes is a ripoff though.... Just saying.

 

The pads' OE manufacturer (my old company) uses an underlayer between the steelbacks and the friction material. They have since 1999, and it's been used on many platforms. The underlayer typically uses a red-orange component, so it's easy to see poor material distribution during production before they get painted.

It sounds more like they would do all four wheels at that price. A discounted parts price for all that comes to about $2400.

 

There is the possibility that the tech was exaggerating the problem. I do have more trouble braking, so I'm guessing that the pads at least need to be changed. And at 132,000 maybe new calipers in the rear are worthwhile. I'm just curious if there are better ones for the truck, like the calipers on the big brake kits for cars.

 

The dealership may want to o a full monty so there are no short-term issues if the slides or pistons are hanging up or on the verge. It's better for them rather than a comeback. Also depending on how badly the pads have worn down, they may have taper worn, and the rotor surfaces may have been gouged. This is especially true of the inner surfaces, if one piston is hanging up.

I found some images of HD pads from my old company which show the underlayer used between the friction material and steel backs. These pads were not production painted, if that is the red coloration the tech reported, and not rust.

Pre-production parts; poor distribution of the underlayer due to being done by hand with a screed rake. The edges of the die cavity tend to have a berm of material rising above the bed so it's higher on the edges. And the more you rake, the heavier constituents move to the bottom and you lose consistency of the mix.