[gm4life08]

Check this out and give it to your dealer:

https://static.nhtsa.gov/odi/tsbs/2020/MC-10184490-9999.pdf

That describes your noise exactly, right down to the driveway. I was unable to locate any TSB for "leaf spring coating" which is why I am fairly sure they were yanking your chain on that one.

I usually adhere to the "if it ain't broke don't fix it" philosophy, but noises can be annoying. If it's any consolation, the only time my truck ever went in for warranty service was for a squeaky driveshaft seal. But the dealer would probably have never known what to do if I had not provided them with the TSB# that GM had issued over a bad batch of seals from the factory. If you hear a noise and cannot figure it out, it is always worth searching the TSB's before taking it in...because I guarantee you most dealer techs won't even bother.

That was the very first TSB that came up in my search for suspension related TSB's.

2020 GMC CANYON PU/CC 4WD

www.nhtsa.gov

Thank you, I appreciate that!

 

[gm4life08]

You mentioned towing is it possible that whatever you have been towing has excessive pin weight? I believe it's possible that could cause compression to a level greater than expected which could cause the rubbing/cracking of the coating.

No towing yet. I haven’t even been within 100 lbs of max payload either. This will be a change in the coming year or two. Good call out though!

 

[gm4life08]

2015-2021 Colorado and Canyon clunking sound heard from...

Here is something new from GM. https://gm-techlink.com/?p=14231

www.coloradofans.com

Thanks. This is describing the same thing that was just shared in the thread by another kind poster with a link to NTHSA instead.

 

[gm4life08]

OP, It looks as though you have the same exact truck and the same exact problem that I had. I brought mine back to the dealer for repairs at 600 miles

My dealer did two things to fix the noises. 1- there are plastic/rubber dampers in the spring packs that are supposed to reduce noise - the dealer found that the ones on my truck were the older style and replaced them with the latest version. 2- they found excessive end play in the rear axle and replaced the c-clips with revised versions. There may be TSBs on both of these issues, but if my dealer was able to figure it out, I have to assume that yours will be as well. They might just need a little shove in the right direction. Totally solvable problems if the dealer cares to solve them. Good luck.

Jeff

Thanks Jeff. I will be sure and let everyone know how it goes. Thanks all for allowing me to vent my frustration/disappointment.

Appointment with a senior service tech (ie not the guys doing quick lube stuff) is scheduled for a couple weeks... At a time they could provide a courtesy vehicle. Fingers crossed second time is a charm.

 

[ApproachMedium]

I was having all kinds of squeaks and clunks from the rear of my truck that the purchasing dealer did nothing about. My truck sounded like a 50 year old POS going down the road. If the noises you hear change depending on the brakes being applied or released it could be the brake pads. I paid another dealer money to perform some kind of "fix" according to a TSB that got rid of the noise for 2 months. They basically greased my rear brake pads. When it came back i greased the pads with salt water proof grease we use for boats. that helped for almost a year. The noise came back and i recently replaced my rear pads as they were worn down. Since then the noise has been completely gone. I did not add any grease to the new pads, which i got from NAPA not GM.

I still would check the TSB against the rear axle for play though, its a possability!

 

[rotaryenginepete]

I was having all kinds of squeaks and clunks from the rear of my truck that the purchasing dealer did nothing about. My truck sounded like a 50 year old POS going down the road. If the noises you hear change depending on the brakes being applied or released it could be the brake pads. I paid another dealer money to perform some kind of "fix" according to a TSB that got rid of the noise for 2 months. They basically greased my rear brake pads. When it came back i greased the pads with salt water proof grease we use for boats. that helped for almost a year. The noise came back and i recently replaced my rear pads as they were worn down. Since then the noise has been completely gone. I did not add any grease to the new pads, which i got from NAPA not GM.

I still would check the TSB against the rear axle for play though, its a possability!

Here's your TSB for the brake pads, I did not list it because the squeak/rattle didn't fit his noise description.

https://static.nhtsa.gov/odi/tsbs/2020/MC-10171267-9999.pdf

 

[MrCamo]

Check this out and give it to your dealer:

https://static.nhtsa.gov/odi/tsbs/2020/MC-10184490-9999.pdf

That describes your noise exactly, right down to the driveway. I was unable to locate any TSB for "leaf spring coating" which is why I am fairly sure they were yanking your chain on that one.

I usually adhere to the "if it ain't broke don't fix it" philosophy, but noises can be annoying. If it's any consolation, the only time my truck ever went in for warranty service was for a squeaky driveshaft seal. But the dealer would probably have never known what to do if I had not provided them with the TSB# that GM had issued over a bad batch of seals from the factory. If you hear a noise and cannot figure it out, it is always worth searching the TSB's before taking it in...because I guarantee you most dealer techs won't even bother.

That was the very first TSB that came up in my search for suspension related TSB's.

2020 GMC CANYON PU/CC 4WD

www.nhtsa.gov

This post unlike anything I have added is actually helpful and may get you back into your truck. Good luck dude I’m outta this one before I get out of hand. (Unless I can actually help)

 

[ApproachMedium]

Here's your TSB for the brake pads, I did not list it because the squeak/rattle didn't fit his noise description.

https://static.nhtsa.gov/odi/tsbs/2020/MC-10171267-9999.pdf

Yep they did that... and charged me for it. It didnt last either. Oh well!