Vibration coming from under my dash, any ideas?

[staynlean]

Well, on my 08' PF it's some where "in" my dash and over towards the px side. The sound starts at about 50mph (no noise whatsoever under this speed.) Vehicle has never been wrecked, no mods or anything like that.

It sounds very similar to static that you would hear from a bad speaker or an electrical short. (I'm just describing it, I do not have a bad speaker or an electrical short.)

I believe it is related to wind noise considering it starts faintly at 50mph, gets a little stronger with more speed but I don't think it is something lose because hitting bumps has no more or less effect on the noise at all.

Almost like a small rock rattling around in a tin can, very strange. Anyhow, I have only tried a few things so far. With my wife driving I have done the usual pressing around on the various dash pieces and also checked under the hood for anything lose but it is most definitely on the "inside" of the vehicle.

So, thought I would post this and let it go for a week or so until I start taking the dash apart. I'm an aircraft mechanic (former auto mechanic) so the work is not an issue, figuring the source out is.

[skinny2]

I have something similar on mine...been there a couple years at least. I only notice it at higher speeds and really seems wind related. It's not always there...I've looked around the windshield cowling but it does sound a little lower. Maybe around the mud guards or fender lining? Honestly haven't spent a bunch of time on it as I just crank up the radio when it shows up, but of course wouldn't mind figuring it out. It seems like if I could drive with my head under the pax side dash it would be easier...but haven't figured out a way to do that yet

[doctahjones]

if you turn the ac/blower off and hit the recirc button, does the sound go away? if so it's the blower motor.

i've found that if you're driving hwy+ speeds that there's a good deal of air that still enters the cabin through the vents if you don't have it on recirc. also makes "low" more of a medium blow if you have the air on and vent open.

also maybe check the cabin filters? maybe there's a rock somewhere in them?

[staynlean]

Yes, I have cycled the blower motor and recirc button back and forth and it has no more or less effect either on the noise.

Also, like post 2 says, it's not always there. However, it is becoming more common and almost always there now. It's most def under the dash, px side, close to windshield and sounds like static (but it's not.)

I might have some time tomorrow to start tearing things apart, I will keep this thread up-dated and if I find the cause I will post some pics.

Anybody else got any ideas?

[skinny2]

The recirc mode sounded like a real possibility. Thinking about this more...lately mine has not made this noise at all when I'm on my way to work...but does it on the way home. Temp related perhaps...it's been 20-30 in mornings and 50's in afternoon. Reminds me I haven't changed out the cabin filter in forever...I think that was this vehicle anyway. We have a cabin filter right??

[volvite]

I have a similar noise. It's not always there and I can't tell if it's temp related or not. I don't think it's the blower motor or any part of that system. I think it's a piece of plastic that is rattling in the dash somewhere.

Skinny2, yes there is a cabin filter. I replaced mine, thinking there was a rock or something in the vent system that was making the noise, however I was wrong. Nothing there and I still have the noise.

[staynlean]

I was thinking blower motor too but the noise is well above that and almost at the top of the dash area.

Of course today I did not have time to tear things apart.

Also, as some other posters have mentioned, I think it is possibly temp related. I had absolutely ZERO sign of this noise all summer long and now it has cooled off and the noise is very much there every day almost.

Everybody keep chiming in please, these are all great ideas.

EDIT* I do have a 2 year old girl that likes to pick up EVERYTHING including little rocks and we are known to hang out in the truck on nice afternoons cleaning it up and what not and all the time she is just crawling from front to back. Would not surprise me if she has dropped a rock down one of the vents or down the defrost vent in the dash.

Lol, I will figure this out.

[volvite]

I have a 3 yr old, but I have not allowed him to crawl around up front yet, so I don't think my issue is a rock unless my wife did it.

[staynlean]

Dash apart, still nothing found yet. Getting frustrated

[staynlean]

*FIXED* So, whoever had the truck before me had a windshield put in it, guess it was not done properly and the seal on the px side all the way up the pillar was causing some wind noise.

The windshield never leaked water in the rain and the seal visually appears to be seated properly but something is not right on the inside.

Currently I just have it masked off with tape up that pillar, guess I will find some kind of sealant to put there.

No chattering noise sure is comforting though, too bad I ripped the dash apart before I put the tape on the windshield. Oh well, wind noises can really throw you for a loop when trying to diagnose them, I would have never thought that it was coming from this location.

Any suggestions on a sealant, I have never replaced a windshield.

[volvite]

Pics of where you put the tape. I want to give that a try. As for sealant, hit your local car parts store and they sell 3M window sealant and such you could use.

[staynlean]

Pics tomorrow, it was dark earlier this evening when I did this.

WORLD OF DIFFERENCE, I can not believe it...

[Clay350]

Guys,

I had same problem and it was related to low temps and highway speeds. Mine was 100% the molding below the windshield near the wipers. It was not tihgt and buffeted at speed. I put a little two sided tape under it to brace it and never came back. Dealer tried to tell me entire dash needed to come out and would not agree with me that it was an external noise. Deushbags

[staynlean]

^Yes sir, after *further* investigation my problem is EXACTLY as you stated. I played around with putting the tape in different areas for a day each or so and narrowed it down to that piece of plastic molding.

And for some weird reason the colder air makes it sound much much worse. Glad you fixed yours too, such an annoyance!

[volvite]

I'll have to look and see. I've not heard my rattle/noise for the past week or so and it's been cold so not sure what to make of that.