Mystery clunk on passenger side- solved!!

Hey all,
I wanted to share this with you in case anyone else is having the same issue.
For a couple of years now I've had an annoying clunk coming from the passenger side when I went over bumps.
I installed new coil overs and upper control arms but that didn't fix it. I went to the dealer and have them look at it, they couldn't find it either. Today I found the issue! I am guessing that at some point the passenger air bag was replaced because there are two bolts missing that should hold the assembly in place under the dash.

In the photo, i have removed the glove box and this is the view up under the dash. In the center you can see the air bag unit, but the two brackets on either side are missing bolts. I can move the whole thing a few inches in either direction and even replicate the clunk I was hearing.

 

Oh man that's not good, did you find two bolts to use?

 

Is there a history of the air bag begin deployed?
Glad u found it

 

Curious about that too. Outside of deployment replacement, only reason it would be loose like that is maybe someone had the dash out to do a heater core/evap core and forgot those bolts when going back together

 

Someone was trying to reduce weight

 

Ha! Definitely looks like a weight reduction mod.

I'll have to look at service history to see if airbag was replaced or worked on

I have a bolt that is the correct diameter but the thread pitch is off. It won't go in and i don't want to force it.

 

The bolts will be either M8x1.25, or M6x1.0 of the appropriate length, my bet is the former.

The open hole in the top right of your photo is where you removed a bolt for the glovebox, correct?

 

Okay thank for the heads up on bolts! That is a big help.
Correct- the open hole at the top of the photo is related to the glove box

 

And M8x1.25 for the win!!
Thanks for the suggestion

 

Many years ago a friend had a nasty rattle in the back rear quarter. He tried for years to find it with no success.

Finally he had a garage gas torch cut a hole in the rear quarter panel.

Apparently during assembly and welding up of the body and frame at the factory, some SOB stuck his Coke Bottle in the body/frame space.

 

WTF?!
Sounds like the factory worker was disgruntled or just a jerk. Either way, that's crazy!

 

I have similar noise. going to check this once rain stops.

 

Did you take a look?

 

haven't had the chance

 

Oh man, need some help here guys and gals.
I am thinking that the previous owner intentionally removed the two bolts that hold the passenger side airbag in place in order to eliminate or at least minimize a rattle.

Once I replaced those two bolts that were missing, the clunk that I was hearing went away but has been replaced by a nearly constant clicking as I go over every little bump in the road.

Wondering if there could be something loose inside the airbag unit???

 

If it was mine - I'd take the bolts back out and put on soft rubber washers on the bolts. hand tighten + 1/2 turn. Otherwise - disable the ABS pull it and see what's wrong when it's out.

 

Good call- I'll pull it out and see if the noise goes away

 

I had a clunking/popping issue with my '14 DCLB since new. I took it to the dealer and they couldn't replicate it. I recorded it with my cell phone and emailed the video to him. They had it for a week and found it!

When driving with one wheel off camber, it would do it. They actually ran my right front wheel up on a pile of snow in the parking lot and it would do it every time. They determined that it was the rear cab mount on the passenger side. They replace both left and right mount and the problem was resolved. With 15k on the truck, they said that there was as much play in the mount as you would expect after over 100k. Obvious this is a mfg defect.

 

Good to know! I have a similar sound on my passenger side that comes from underneath the truck. The dealership of course blames my Icon coilovers and UCA's. But the problem existed before I install those. I'll take a look at my cab mounts on that side. Thanks!