discgolf01

Side question: how many miles did you have when the shock failed?

Yes, it's easy. Highly recommend these 2 purchases to make it an easy 1 man job: https://www.amazon.com/dp/B000TK9FE8?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_9&th=1 https://www.amazon.com/dp/B07L52B4CX?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_9

Update: Replaced the AC Delco pads with Powerstop ceramics https://a.co/d/hq4FdEv Redid the same run with multiple points of aggresive downhill breaking and so far so good, no noise. Long story short: I don't recommend the AC Delco Gold front pads due to noise when hot.

Update: Pulled everything back off, cleaned the slider pins, pad clips, removed the adhesive that Delco put on the back of the pads, cleaned up the residual adhesive on the caliper, greased everything back up, including the backs of the pads, and swapped pads from left to right. Did some agressive downhill stops to get everything warmed up and the same noise returned. Happening at different speed then before, but still there. So I guess next step for me is to ditch the AC Delco pads and go aftermarket. Was thinking the PowerStop Evolution Plus ceramics - anyone have any recommendations? No trailering, definietley not a sport truck, don't care too much about brake dust, just looking for good stopping and zero noise. Thanks!

Bumping, and adding that this noise only seems to happen after the brakes have warmed up, zero noise at any speed when cold (outside air = 55F) and in the first 5 or so miles.

The pads were AC Delco gold and had something I've never seen on pads before: they had a blue plastic film on their backs that said remove before installing and under the film was a sticky substance on the back of the pad. Because of this, I did not grease the back of the pads because I was thinking they wanted the pad to stick to the caliper piston when they retract from the rotor? Every pad replace I've done on my cars over the years have never had any sticky substance on the back and I've added grease between them and the pistons. The sticky substance was definitely intentional and covered all of the back of the pads (both inners and outers). Interestingly, I replaced the rear pads a few months ago, also with AC Delco gold parts, but the rear pads did not have this sticky substance on their backs.

I knew I forgot something. Both pads and rotors were AC Delco gold. Updated the original post with the info, thanks.

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Hey guys, so ended up replacing both front rotors and pads to fix a pulsation issue. Took it out and did the sequential 40mph to 10mph hard brake 4 times to set the pads to the rotors. 2015 Sierra 1500 crew cab, 5.3L, 60k miles. New pads and rotors were both AC Delco gold. Within the next day or so, started hearing a very high pitch obviously metallic noise coming from the left front. How it started: -Very light braking, only at very beginning of the brake pedal travel -Only under 10 mph -Almost instaneous, a very quick "chirp" then it would be gone -Harder braking and this noise would not happen What it is now, approx 150 miles later -Happens at braking at 40mph -Noise usually lasts all the way down to 25 mph -Approx first 25% of brake pedal travel -Harder braking makes the noise go away -Occiasionally the noise can be heard all the way down to full stop. Interesting to note that when it does happen at very slow speeds (under 5mph), and therefore slow rotor RPMs, the noise is cylical, meaning on/off/on/off, not consistent. This seems to me it would indicate something on the rotor, but is only heard when that part of the rotor touches the pads. My first thought with the high pitch metallic noise was the pad clips, but I doubled checked all of them during replacement (new clips) to make sure they were in the proper position and full installed to the bracket, maybe one came loose/moved? Was hoping to get thoughts from others on this before I dive back into them, as my next step was going to swap pads left to right and see if the noise follows the pads or stays with the left rotor. Thanks in advance!

Update: replaced the front rotors and pads and vibration is gone. Lesson learned: the fronts can cause vibrations not felt in the steering wheel. I'm wondering if the steering design has some sort of damping/isolator in it since the pulsation I was feeling was fairly light and the only vibration I felt was through the frame/seat. New issue: there is a slight metallic ping from the front left when braking from 5mph to 0. It lasts for only a fraction of a second at 5mph then disappears. Only thing I can thing of is the abutment clips on the pad, but I double checked each one was installed exactly as it should be before installing the pads. I did the 40mph to 10 mph stops four times to seat the pads. I'll give it some time to see if it changes/disappears. Any thoughts from anyone?

I've heard that "lazy" or slow retract seatbelts are mostly due to a buildup of skin and grease from the occupants. Have you tried to clean with something geared more towards cutting grease? Even something like Dawn? Plus you want to extract the entire belt, clean, and then leave extracted to really make sure its dry before it coils back up.

Thanks for this info. Guess I'll do the fronts next. Its just that not feeling any pulsing in the steering wheel is nagging me.

Update: Finally got around to replacing the rear rotors and pads. Problem still exists: a pulsating vibration through the body/seat at light braking at highway speeds. Still nothing being felt directly through the steering wheel. Also, tires were rotated during the brake work. Anyone have any ideas? Could it really be the front rotors even though nothing is being felt through the steering wheel?

Great, thanks for info. Had a feeling it might be just the rears, but have never had a vehicle where just the rear rotors go out of whack and not the fronts. Anyway to 100% verify it's the rears without replacing them first?

Hey guys, looking for some advice on some pulsation I am feeling while light braking at highway speeds. Normally, I would just assume it's the front brake rotors out of whack and replace them and the pads, but in this case, the pulsation/shaking I am feeling is not coming through the steering wheel like I've always felt before with rotor issues on other vehicles I've owned. This pulsation is felt through the seat/vehicle, nothing through the steering wheel. As mentioned, this occurs with light braking at speeds over 50mph and then dissipates the harder I brake. Pulsation is light, most would probably not notice it, but I do since I've owned the truck since new. Any thoughts on this? Might it just be the rear rotors having an issue since it's not being felt through the steering wheel? Thanks! 2015 Sierra crew cab 5.3L 60k miles