Mysterious Clunking! [Solved] - Chevy Impala Forums
Chevy Impala 8th Gen Discussion W-Body 2006-2013 (2014+ Limited). Discuss all Chevy Impala 8th Generation Performance and Technical Discussion here.

User Tag List

 7Likes
  • 4 Post By TeeRev
  • 1 Post By 12 lt
  • 1 Post By jtrosky
  • 1 Post By jtrosky
 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 03-19-2019 Thread Starter
Senior Member
 
TeeRev's Avatar
 
Join Date: Nov 2016
Location: Indiana
Posts: 598
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 124 Post(s)
Thanks: 15
Thanked 76 Times in 70 Posts
Garage
Mysterious Clunking! [Solved]

So, about the mysterious clunking I mentioned in the "What Did You Do to Your Impala Today" thread...

About three weeks ago, every once in a while I'd hear this "clunk" coming from the back of my car when braking. It didn't happen all the time, and it wasn't 100% repeatable. Of course, it was driving me nuts. It seemed to be coming from the back right of the car.

I checked the wheels, the brakes, the suspension, nothing. Then the sound went away and I didn't think anything more of it. But... the sound came back a week later. When braking and sometimes letting off the brakes at slow speed, there'd be a clunk. Clunk. Clunk. Clunk. Drove me absolutely insane.

Finally, and I don't know why it took me this long, I decided to see if it could be something within my trunk. So I emptied it out, yanked the mat and carpet, checked the spare tire well, nothing. Then I looked at the side, and guess what I found?

A veritable swimming pool in my trunk. With a foot-long (literally) chunk of ice floating around. The backwards / forwards motion of braking would cause the water to slosh around and the ice would hit the body, causing that "clunk" sound. The reason the sound was only present for a day, then went away for a week, then came back was because it finally got over freezing outside.

There was no water anywhere else in the trunk, or in the "well" on the opposite side. I know the water didn't come from the top (i.e. the tailight area or the trunk lid) as I have a waterproof mat that covers the entire trunk floor, and the carpet and sides were completely dry. It must have been a bottom-up splashing of water, I believe from the vent (black plastic vent in the side wall over the puddle). I must have scooped out 30+ oz of water, not including the hunk of ice.

I wish I had taken a better picture of where the swimming pool in my trunk was located. Best way I can describe it is that it is in the back right corner of the car. Just behind the passenger side rear wheel.

Has anybody else on this forum experienced something similar?
Attached Images
   


08 Impala LTZ


Rosen DS-GM1010-P11
Rosen DP-1088
Blackvue DR-470 2-Ch w/ PMP & GPS
Ultragauge MX 1.3
Dynomax 3" tips
Chevrolet Performance STBs + DR custom brackets
30% Llumar tint
Techno Steel interior trim / leather shifter
SS grille
Reverse light / full interior / instrument cluster LED retrofit
LED headlights / fog lights
Stant locking gas cap
WeatherTech front liners / window deflectors
GM molded splash guards
McGard locks
Firestone Firehawk Wide Oval UHP
TeeRev is offline  
The Following 2 Users Say Thank You to TeeRev For This Useful Post:
12 lt (03-19-2019)
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 03-19-2019
Senior Member
 
12 lt's Avatar
 
Join Date: Feb 2017
Posts: 1,061
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 241 Post(s)
Thanks: 73
Thanked 85 Times in 80 Posts
Garage
Thanks for sharing. Seems a strange place for water to get in. Have not had that issue, but will be certain to remember this.
sheila likes this.

My 6 year constantly asks why. What adults can learn from 5 and 6 year olds, to listen with your ears and mind open. Hard to learn when you don't listen ......
12 lt is offline  
post #3 of (permalink) Old 03-19-2019
Super Moderator
 
jtrosky's Avatar
 
Join Date: Jun 2013
Location: West Grove, PA
Posts: 12,431
Mentioned: 76 Post(s)
Tagged: 0 Thread(s)
Quoted: 932 Post(s)
Thanks: 992
Thanked 2,307 Times in 1,803 Posts
Garage
My guess is that it came in the little vent. I've seen those before - I think it was with @LazerBlue's Impala? Maybe from a car wash (high pressure water making it's way into that vent)? Or if you drove through high water?

That vent is these to supposedly let air out (like when you close your doors with the window up, the air pressure inside the car gets relieved somehow - through that vent - at least that is my understanding of why it's there...
2016LimtedLTZ likes this.
jtrosky is online now  
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 03-20-2019 Thread Starter
Senior Member
 
TeeRev's Avatar
 
Join Date: Nov 2016
Location: Indiana
Posts: 598
Mentioned: 9 Post(s)
Tagged: 0 Thread(s)
Quoted: 124 Post(s)
Thanks: 15
Thanked 76 Times in 70 Posts
Garage
Quote:
Originally Posted by jtrosky View Post
My guess is that it came in the little vent. I've seen those before - I think it was with @LazerBlue's Impala? Maybe from a car wash (high pressure water making it's way into that vent)? Or if you drove through high water?

That vent is these to supposedly let air out (like when you close your doors with the window up, the air pressure inside the car gets relieved somehow - through that vent - at least that is my understanding of why it's there...
Yup, that's how the vent works, I believe, and my main suspect as well.

I haven't driven through high water, but I think you may be on to something with the high pressure underbody wash at the car wash. Good idea.


08 Impala LTZ


Rosen DS-GM1010-P11
Rosen DP-1088
Blackvue DR-470 2-Ch w/ PMP & GPS
Ultragauge MX 1.3
Dynomax 3" tips
Chevrolet Performance STBs + DR custom brackets
30% Llumar tint
Techno Steel interior trim / leather shifter
SS grille
Reverse light / full interior / instrument cluster LED retrofit
LED headlights / fog lights
Stant locking gas cap
WeatherTech front liners / window deflectors
GM molded splash guards
McGard locks
Firestone Firehawk Wide Oval UHP
TeeRev is offline  
post #5 of (permalink) Old 03-20-2019
Senior Member
 
Joes74challenger's Avatar
 
Join Date: Apr 2016
Location: Fort Wayne
Posts: 1,310
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 255 Post(s)
Thanks: 30
Thanked 122 Times in 118 Posts
Garage
weird thing is i always had the underbody washes done on my 2010 and never had a water issue in the pockets (i checked them periodically and they were always dry.
Joes74challenger is offline  
post #6 of (permalink) Old 03-20-2019
Senior Member
 
plano-doug's Avatar
 
Join Date: Aug 2009
Location: Plano, Texas
Posts: 2,622
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 382 Post(s)
Thanks: 131
Thanked 380 Times in 355 Posts
Quote:
Originally Posted by Joes74challenger View Post
weird thing is i always had the underbody washes done on my 2010 and never had a water issue in the pockets (i checked them periodically and they were always dry.
It would have to be a lucky shot. But I've seen sprayers before (in a bottle washer at a soda plant) where some of the jets get wonky such that an extra strong stream can be coming out. It would only have to hit the target for a moment to deliver enough water to make the icicle TeeRev posted.

Doug

.
plano-doug is offline  
post #7 of (permalink) Old 03-20-2019
Super Moderator
 
jtrosky's Avatar
 
Join Date: Jun 2013
Location: West Grove, PA
Posts: 12,431
Mentioned: 76 Post(s)
Tagged: 0 Thread(s)
Quoted: 932 Post(s)
Thanks: 992
Thanked 2,307 Times in 1,803 Posts
Garage
Keep in mind that it's just another off-the-wall "JT theory", so it is VERY possible (maybe even probable) that it's completely false... ;-)
plano-doug likes this.
jtrosky is online now  
post #8 of (permalink) Old 03-22-2019
Member
 
dtnel's Avatar
 
Join Date: May 2015
Posts: 96
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Thanks: 3
Thanked 11 Times in 10 Posts
I've had a clunk for years and it's not water related. It's suspension related I believe. Replaced rear struts with a quick strut kit, replaced stabilizer links, the lower easier to replace cross beam bars, the forward to front of axle lateral bars. Only thing I haven't replaced is the sway bar. Replaced the bushings at the same time I did all the other stuff.

It is mainly worse when people are in the rear seats , 1 or more people and the lore the worse the sound. Wheel bearings, brakes and rotors have also been replaced. All this was done as a 10 year complete suspension rebuild which was roughly $1200 in parts including the front rack & pinion, front quick struts, front sway bar and sway bar links. This didn't include an alignment afterwards which was around $70 or so give or take.

Sent from my SM-N960U using Tapatalk
dtnel is offline  
post #9 of (permalink) Old 03-22-2019
Junior Member
 
Replays's Avatar
 
Join Date: Jan 2019
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by dtnel View Post
I've had a clunk for years and it's not water related. It's suspension related I believe. Replaced rear struts with a quick strut kit, replaced stabilizer links, the lower easier to replace cross beam bars, the forward to front of axle lateral bars. Only thing I haven't replaced is the sway bar. Replaced the bushings at the same time I did all the other stuff.

It is mainly worse when people are in the rear seats , 1 or more people and the lore the worse the sound. Wheel bearings, brakes and rotors have also been replaced. All this was done as a 10 year complete suspension rebuild which was roughly $1200 in parts including the front rack & pinion, front quick struts, front sway bar and sway bar links. This didn't include an alignment afterwards which was around $70 or so give or take.

Sent from my SM-N960U using Tapatalk
Funny my 2012, which has a long nightmare story I’ll tell if I can ever get time(electrical, trans, speedometer, traction control, hubs, stabilitrak, and many more general electrical problems), had a clunk that sounded like coming from under car toward rear maybe even right under passenger seat and was driving me crazy. Checked all suspension, brake system, all bushings, etc. and couldn’t pinpoint it.

Next focused on exhaust because was more evident on bumpy roads and sounded like it could be muffler bouncing around, found nothing.

Finally had car in air repairing the electrical problem mentioned above and just started pushing/pulling on everything under car. Was the dang shield over gas tank. Hit it with my hand and it clunked. At front of tank the shield was sitting against underbody of car and every time car hit a bump or driving fast on uneven roads the shield would come off the body and slam back against it. Popped push-ins out that were closest to that area, shield dropped down some, little light bending there and opposite end to make it sit flat against tank again and not touch underbody in any way, and noise is gone.

Been a mechanic 30 years and I have never seen such a thin piece of metal make such a loud noise. Noise sounded like someone hitting something in rear end with a small hammer.

I’m not sure what gens have the shield but if it does check all the way around it and tank to see if shield is touching body anywhere. Can’t remember if my 2010 had the shield or not, been a while since was under it and it has moved on thanks to a deer on a long dark highway. And sure can’t remember if the 2004 had it, that was way too far back lol. Damn I’m getting old. Anyway, just trying to say don’t discount the shields that cover everything under the car, I did at first and it cost me a few months of frustration before I finally figured it out.

Will get back when have more time to tell the story of the 2012. Wanted to share because this forum has helped me tremendously over the years. Always been in such a hurry never even created an account until a couple months ago. So feel like it’s time I give back a little since have to slow life down some, or more accurately life is slowing me down.

Last edited by Replays; 03-22-2019 at 08:40 PM. Reason: Fixing my errors
Replays is offline  
Sponsored Links
Advertisement
 
Reply

Related Threads
Thread Thread Starter Forum Replies Last Post
06 Impala Clunking noise rear suspension dtnel 8th Gen Suspension 1 03-22-2019 06:57 AM
2014 LT Limited Front Right Wheel Clunking evil ken 8th Gen Drivetrain 2 07-02-2018 09:58 AM
Odd clunking & CV axle hard to rotate Black_Pearl_2012 8th Gen Drivetrain 0 05-12-2018 02:25 PM
Clunking noise Bobbyjoes55 8th Gen Suspension 15 12-09-2017 12:11 PM
Mysterious Ground Wire priceless819 Chevy Impala 8th Gen Discussion 0 07-27-2017 08:50 AM


Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome