2021 Chevy Traverse uneven pad wear

[JTK]

My darling bride notified me at 6pm yesterday that her Traverse is making a bad scraping noise from the front. "It started last week, went away, now it's back and constant". I took it for a quick test drive and only had to go a couple hundred feed to know it was brake related and coming from the front right. I peeled the front right wheel and caliper to find the outside pad nearly new and the inside worn right to the metal. The caliper pins were nice and free and the pads were not badly seized in place. I was able to pop them out fairly easily. They were GM pads that I think were replaced when I bought the vehicle used in Jan/Feb 2023 with ~32K miles on it from a GM dealer. I believe the rotors were factory. It currently has 53K miles. Given Advance Auto was open until 9pm and had parts in stock, I went with what they had. CarQuest coated rotors and a CarQuest premium ceramic pad kit. $288.15 all in.

The way they wore puzzles me. I've had similar wear on other make/models before, but it was always the result of a stuck pad or pin and they'd be worn crooked, etc. The outside of the rotors looked perfect, with even wear, as did the pads. The inside of the rotors had tons of meat left, but the surface was an absolute atrocity.

It's been awhile since I did a brake job on a GM product. I really like the style of abutment clips these use. They hold the pads nicely so they don't go flying onto the floor.

 

[Analog-1]

Caliper pins are dry of grease and not working as they should.

 

[JTK]

Caliper pins are dry of grease and not working as they should.

Like I said, surprisingly they were very well lubed and moving freely. I disassembled, cleaned and re-lubed with 3M pure silicone grease anyway, as I would with any brake job.

 

[Rand]

I'd have figured 4 years of buffalo salt.

 

[JTK]

I'd have figured 4 years of buffalo salt.

Oh there was!

There was only very light corrosion under the abutment clips surprisingly. Of course the aluminum wheels were corroded onto the rotors badly and the rotors were corroded to the hubs. Some of the lugnuts are swollen with the outer jackets cracked and they were on crazy tight. My big Millwalkee E-impact strugged. I broke the T30 rotor hold down screw on the pass side trying to remove it and had to drill it out. I got the driver side T30 screw out OK, but thought that one would break also. The 21mm caliper bracket bolts were held in with a light blue thread sealant. Those took a 2 foot breaker bar and lots of force to move.

South Main Auto style, I use my Meuller-Keups file to clean the abutment clip area on the caliper brackets, right down to bare metal, then apply hi temp brake grease, then the abutment clips.

Even though everything was moving freely (pins could have been left as is), obviously something wasn't able to move enough.