strange tahoe noise...

[jrneyman]

Ok..I have been dealing with this for months now, and im sick of it;
noise is hard to describe...it's an intermittent vibration "waah waah" noise, that seems to come from somewhere under the passenger side of the vehicle; it happens in cold and hot weather, but particularly after its warm; only happens during idle, and i can make it do the noise, by increasing the rpm to 600, which is only 100 rpm over idle speed.
Thought it was the pass side running board, so i took it off-still there-
I have been under this truck for days and still no luck--
My opinion on the sound is that its almost a sound like an exhaust shield or flimsy piece of metal vibrating-it started this 2 weeks after i bought it, back in sept of 07....Any ideas would be appreciated-at this point i'm willing to try anything but takin her to the stealership!
M.

 

[M.M. 700]

I had a similar deal with my HD. Found it to be the thin tin (?) shield over the top side of the muffler. I had to look close but the front inside spot weld was cracked. Rattled like hell, at a certain RPM.

Did you have someone rev it to the 600 RPM, and have you listening under the Hoe?

 

[jrneyman]

Thanks...and yes i have, but i really couldnt determine where it was coming from.
i know exactly the piece of metal youre talkin about, and ill check that out this weekend--
i have had my brother(whom i trust really well) rev it to 600 while i listen for it--thanks for the info!
M.

 

[dropmech]

If it is the shield, it could be as simple as picking up some high temp RTV and squirting some in the cavaties.