A rumbling/growling noise started on my 2006 with a 2.4 automatic. I thought it might be the fan motor so I turned it off and the sound was still there. I thought it could be the exhaust flex connector but it only makes noise with the wheels turning. I put it in drive and hold the brake while slowly revving the engine to put it under load and no noise. I drive it and the noise starts at about 20 mph.

I figured it had to be wheel bearings so I put it on jack stands with the front wheels off the ground and ran it. I could hear the noise inside the cab but not outside. I got under the vehicle and listened with a stethoscope to each spindle and did not hear the noise. I checked at the transaxle where the axles go in and no noise. I put the stethoscope tube by the exhaust flex connector and no noise. I listened to the transmission and no noise. Checking around the engine compartment I heard some bearing noise from the tensioner pulley. I removed the belt and the noise is still heard inside the car but not under the hood. I propped the throttle against the seat to hold the speed up to 40 and checked everything again from under the vehicle. Again no noise. The cooling fan wasn't running while the noise was there. I turned the AC on to run the fan and there were no abnormal noises.

With the engine off and the brake calipers pried back to stop the pads from rubbing, I checked the wheels for play and found none.

If it was an older car I'd blame it on a speedometer cable needing lubrication because that's what it sounds like.

I'm wondering if there is a relay that is energized when the vehicle reaches a certain speed that could be buzzing or if there is some vacuum used. It almost sounds like a stripped plastic gear on a motor but I don't know what that would have to do with the wheels turning.

 

Is the circulator fan on?

You can hear it when the car is jacked up? So it could not be rear bearings?

Exhaust pipe/muffler?

Upon returning from a trip My wife asked "what is that noise coming from the luggage?"

I have a razor that vibrates, somehow got turned on. I am really glad we were not flying!

 

I turned the circulator fan for the heater and air conditioner off and it appears to actually turn off.

I also turned the radio off but don't the warning sounds also come through the radio like the turn signal indicators?

I also thought about the fuel lines vibrating but why would that only start at about 10 mph?

I'm taking a 120 mile trip tomorrow. I hope I don't find out what it is the hard way.

 

The chimes will still sound when the radio is off.

CV axles is about all that's left, if you are sure of your troubleshooting.

 

I put 250 miles on it today at 75 mph most of the way. The noise didn't change. I'll put it on jack stands again to see if anything got loose. I didn't try the stethoscope on the outside of the body. Time to change oil anyway.

 

Like a plastic bag stuck on the under carriage?

 

I had that happen a year ago and thought I had a flat tire. When this noise started I immediately thought of that. When I had it in the air, not moving and still making noise, I looked for something wrapped on the axle shafts or an axle boot.

 

Are replies possible?

 

I've typed this reply 4 times and keep getting told to log in again and lose the reply.

I got the hubs and a rotor and pad set with the wrong bolt pattern for the rotors so I had to wait for a replacement. When I got those the fuel line was leaking. I checked with the Dealer and the fuel lines were nearly $1,000 so I considered scrapping the car. Nobody will take one in trade because the issues with these are very well known and dealers figure at least $3,000 to make one legal to sell.

I found a company called Lines To Go that sells the set for $159.95 including shipping so I ordered them.

Once I got the fuel lines, the belt tensioner pulley was making noise so I replaced the tensioner and belt.

I got it in the air and found bad stabilizer links so I replaced those too.

I also changed oil and coolant. I have 50,000 miles on it. I hope that it lasts another 25,000.

 

Doesn't this mean the problem has to do with the circulator fan?