I have a strange vibration/vibrating noise that sounds and feels like it is coming directly below my center console. I thought this was transmission related, however I just put a NEW transmission with a new torque converter in and the noise is still there. In fact it may even be a little more pronounced now. The transmission seems to be working perfect and feels great. The noise and vibration does not seem to change with the RPM or speed of the vehicle. It is not a loud noise or a harsh vibration, but it should not be there at all. It almost sounds like it is coming for the torque converter area but like I mentioned does not change with speed or rpm. It almost goes away when in reverse, and quiets down when in any gear, it is more pronounced when at an idle in park or neutral. Do you guys have any thoughts as to what could be causing this?

Thanks

 

I tried looking a bit more to see where the noise was coming from and it is possible it is coming from the dash, it is really hard to pin point where it is though. It almost sounds like a fan with bad bearings, only it does it whether the heater is on or not and there is no air flow sound with it. The old exhaust fan in my bathroom sounds very similar.
I don't feel any vibration with it, but it has that vibration sound, almost like something is loose and wobbling around.

What do you guys think?

 

1995 GMC Jimmy 4 WD SLT

I would like to hear more about your symptoms.
I have a similar vibration noise.
Vibration Noise is more pronounced while sitting in the drivers seat and vehicle is standing still at idle. Appears most apparent just behind the guages of the dash. Low speed constant city driving within first 5 miles of starting driving my vehicle , I can hear it as well I the interior.
If I open the hood the noise is not as apparent believed b/c of the other engine idle running sound.
If I push the Wiper Motor Unit against the firewall , ( mine is missing lower securing screw ,BTW) I can feel a strong vibration against the Wiper Motor. Then vibration noise sounds similar within the engine compartment firewall. Of course wipers are Off.
Sometimes it even sounds as if Fluid is gurgling , just beyond dash guage area if firewall.
One gentelman suggested the noise is Engine Mount vibration being transmitted to other area(s).

Comments. ?
Thanks for any suggestions.

 

I did a bit more investigative work on it this weekend with a buddy to help try and pin point the noise. I took one of my wife's stethoscopes and listened everywhere I could.
With the truck idling you can only here it inside, I crawled underneath the truck and could not here anything at all. I also tried listening in the engine bay and could not here that noise any where.
In mine it seems to be coming from the center section of the dash somewhere, and I can here through the vents. Turning on the fan no matter what zone it is selected on does not change it at all, and it does not change with rpm or speed.
Every now and again I get that gurgling noise as well. I believe the gurgling is because it is a little low on coolant. I am almost thinking that something has fallen down either into a vent or into the dash somewhere and is rattling around when the engine is running, but I am not sure. I suppose it could be bad motor mounts causing something in the dash to rattle around. However I do not here it at all from the engine bay or under the truck, only from in the cab.
I am still pretty clueless as to what is causing it though, just taking wild guesses at this point. It is starting to drive me nuts though, hopefully can get it figured out soon.

 

I like what you suggested that some foreign object may have fell into the dash through the air vents or through vents , crevices of upper dash board.

Still sounds like our sounds are somewhat similar.
I have new Motor Mounts as of End of last year and vehicle only has 5500 miles on them. I recently took the whole left portion (major portion) of dash board out and cleaned all vents and interior exterior of dash. When replacing couple Dash board idiot light bulbs.
Noise I believe is buried between Dashboard and Firewall or somewhere thereabouts ...
Noise comes and goes some days I don't even hear it ! Strange !

 

Since you have recently had the transmission replaced I would suggest you check the transmission mount connection to the cross member. Could be bad, could be they didnt get it seated properly or it is just loose.

 

I have a 1999 Trailblazer with the exact same sysmptoms as you describe, can only hear it from the inside and some days its doesn't do it at all????
Have looked at everything I can possibly think of but cannot fin anything. Hopefully someone can come up with a solution, its driving me nuts

 

I am pretty sure I have found my unknown noise. Not sure if it is the vibration also, but definetly Found The Noise !
When I went to turn key to On position only to check the temp on the grill thermometer the noise appeared louder this time !
The rotating gurgling sound is coming from the Wiper Motor. With only the key On position and wipers off a little group of mice are spinning quickly inside the motor ! Ha Ha. Then after driving for 10 miles and stopping to park , I let it idle a while and I could hear the quieter mice spinning inside the Wiper Motor unit.
I think this one Noise is solved.

Vibration may be the same culprit or another -
Little bit more sluth work to do . . .