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70+ MPH Rattle

DanielK
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DanielK New Member

DanielK

Posted
Posted (edited)

I've been trying to isolate a dash rattle on my new '19 Silverado LT Crew Cab RWD (edited). 

 

Facts:

  • Rattle starts when going over ~70+ MPH.
  • Rattles more consistently as speed increases.
  • Sounds like metal clanking - almost like a loose screw in a metal bowl.

 

Suspicions:

  • Probably related to wind.
  • May be related to internal temperature - the rattle is more consistent as the drive time increases.

 

Things I've done so far:

  • Dropped it off to a Chevy Dealer Service Center for 3 weeks - they were not able to isolate it. I picked it up because it was getting ridiculous. Will be dropping it off again when they have a loaner car ready on Dec 13th.
  • Removed driver side door panel. No luck.
  • Verified it wasn't the hood latch cable.
  • Verified it wasn't the side mirror.
  • Taped driver side door seams from outside.
  • Taped front window seams from outside.

 

As you can imagine, this rattle is very hard to isolate because you have to be going quite fast to hear it and it's also more consistent as the drive time increases.

 

Here is the link to the video: https://photos.app.goo.gl/WVgswQrfW5hhPwSQ7

 

I'm so perplexed.. Any ideas on what this could be??

Also, any pointers to a good mechanic forum would be greatly appreciated.

Edited by Daniel YS Kim
DanielK New Member

DanielK

Posted
  • Author
Posted
12 hours ago, 2016 Sierra Owner said:

This may be the problem...

 

Mine is RWD. Do you think this applies to me as well?

  • 2 weeks later...
Landry Enthusiast

Landry

Posted
Posted
On 12/1/2019 at 5:22 PM, DanielK said:

I've been trying to isolate a dash rattle on my new '19 Silverado LT Crew Cab RWD (edited). 

 

Facts:

  • Rattle starts when going over ~70+ MPH.
  • Rattles more consistently as speed increases.
  • Sounds like metal clanking - almost like a loose screw in a metal bowl.

 

Suspicions:

  • Probably related to wind.
  • May be related to internal temperature - the rattle is more consistent as the drive time increases.

 

Things I've done so far:

  • Dropped it off to a Chevy Dealer Service Center for 3 weeks - they were not able to isolate it. I picked it up because it was getting ridiculous. Will be dropping it off again when they have a loaner car ready on Dec 13th.
  • Removed driver side door panel. No luck.
  • Verified it wasn't the hood latch cable.
  • Verified it wasn't the side mirror.
  • Taped driver side door seams from outside.
  • Taped front window seams from outside.

 

As you can imagine, this rattle is very hard to isolate because you have to be going quite fast to hear it and it's also more consistent as the drive time increases.

 

Here is the link to the video: https://photos.app.goo.gl/WVgswQrfW5hhPwSQ7

 

I'm so perplexed.. Any ideas on what this could be??

Also, any pointers to a good mechanic forum would be greatly appreciated.

I have taken it to two different dealerships and no fix yet.  Mine happens around 50 mph and occurs about 90% of the time.  I went through the same checks you did.  If anyone has solved this, I would greatly appreciate the help.

  • 2 years later...
Recneps735 New Member

Recneps735

Posted
Posted (edited)

SOURCE OF NOISE FOUND!!! 

 

After many failed attempts, and with hope of finding the source of the rattle on my own diminishing, I decided to get some help from my dad to drive my truck so I could sit in the passenger seat and hear the noise for myself. Armed with a stethoscope specifically made for cars (can be bought off of amazon for like $15 lol), I was sure I was going to find the noise. To knock out two birds with one stone, I went ahead and used some painters tape to seal up the windshield, where it meets with the body/door pillar. Much to my surprise, when we started driving down the road, I couldn't hear the noise. I thought I was losing my marbles lol. 

 

This led me to believe either the seal of the windshield itself was faulty, or the roof molding trim on top was creating the "rattle" noise. This made more sense to me as the sound increased with speed. Even though the molding had a bit of play, I initially threw it off the table because it really didn't seem that bad... That being said, I removed the small bit of tape that I rather unintentionally covered the end of the molding with. Low and behold, the noise returned! I found that the little plastic insert was rattling around and perhaps slapping against the roof of the truck. After taping off the area, I applied a small dap of black silicon under the end and taped it down for it to dry. On my drive to work this morning, the noise was GONE!!!

 

Needless to say, my marbles have been restored, and I know exactly what to look for when the driver side inevitably does the same thing lol. *Whew* All is well again lol.

Edited by Recneps735
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