Help me diagnose this noise, please

[jsindorf]

I've attached a link to a sound file (mp3) of a noise that I hear occasionally while I drive my 99 4Runner LTD.

the link: https://clyp.it/5jqgga1i

I've thought it was coming from under the console, but my wife rode with me recently and said it's coming from the footwell area on the passenger side.

It isn't consistent. Some days I'll never hear it. Other times, it happens a lot. It does not seem to be environmentally dependent -- it happens when it's cold and hot, windy or still, bumpy road or smooth.

I hear nothing until I reach about 42mph, then it starts this metallic, bolts in a tin can noise (listen to the file) and builds in strength until I reach about 65 and then it doesn't get worse, just stays the same loudness.

Here's the link to the file in case you missed it earlier: https://clyp.it/5jqgga1i
(at 23 seconds in, you can hear the noise clearly begin)

I have touched everything I can inside, and feel no matching vibration and nothing inside decreases the noise.

I've crawled underneath and the heat deflectors seem to be secure.

I appreciate your help!
thanks in advance!

 

[KaliKid]

Have you checked the AC fan under/behind the glove box

 

[jsindorf]

No... wouldn't the AC have to be on to hear any noise from it? Or does it bounce around back there and create noise? Where do I look to check this?

 

[GHARP57]

there is a body mount in that area, could it be that?

 

[jsindorf]

greg,
where is that body mount?

thanks!

 

[Tek23]

Does it happen when under a load (acceleration)?

 

[jsindorf]

It first is noticed under load, going to highway speed, it kicks in at about 42mph. But, I can be at speed, 50 or so, and let off, glide down a hill, and the noise remains.

thoughts?

 

[mtbtim]

I would first get under the rig and see if there's anything obviously loose. If you don't see anything, I would inspect your u-joints. U-joints can make a noise like you've recorded when they're going bad. Grab the driveshaft near the double cardan joint and apply force in all directions with your hands to see if you detect any movement/sop in the joint. Do the same with the rear u-joint near the differential. If you don't feel any movement, there still could be a problem with the u-joint but it's just going to be harder to figure out if the u-joint is the cause of the noise.

 

[Tek23]

I would first get under the rig and see if there's anything obviously loose. If you don't see anything, I would inspect your u-joints. U-joints can make a noise like you've recorded when they're going bad. Grab the driveshaft near the double cardan joint and apply force in all directions with your hands to see if you detect any movement/sop in the joint. Do the same with the rear u-joint near the differential. If you don't feel any movement, there still could be a problem with the u-joint but it's just going to be harder to figure out if the u-joint is the cause of the noise.

What he said ^^^ the sound seems similar to the issue I had. Ended up being the double cardan joint

 

[jgue467]

Transfer case dynamic dampner?

If 4wd there is a dynamic dampner on the transfer case that can become loose (two bolts) and rattle at odd times. Some folks tighten it, others remove it entirely and claim not much effect. Luck. :cowboy:

 

[jsindorf]

great... I'll check the U joints / double cordon joint.

Where is the dynamic dampner?

thanks guys...
I appreciate it.

 

[GHARP57]

greg,
where is that body mount?

thanks!

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