Ringing noise only while driving

I have a 2001 Tacoma 3.4. About a month or so ago I noticed a ringing noise (like a ringing in your hear type sound) seems to be coming from the left side of the engine bay but not exactly sure. It never does it in idle. Only when driving. And it always seems to start ringing around 50mph. Then seems to die down after 65-70.

Any ideas from anyone?

 

Could it be a bad speaker picking up distortion? That kind of tone sound?

 

I wouldn't think it would be the speakers. It does it with the radio on or off. But I have noticed whenever it's wet or raining out, you don't hear it...

 

A Audiologist might be able to help you.

 

Yes. I've read another guys post on here and he took his truck and had them hook up something to it so they could find out where it was coming from. He said they heard it but never could pin point where it was coming from.

 

Maybe an injector? My old 22RE had some whiny injectors.

 

Is it the same, no matter the RPM ?

Try dropping down to neutral (very carefully) while going 65, and see if the noise still occurs while slowing (while coasting) to 40. If it still happens at the same speed, then its not the motor, and I would look at wheel bearings or tires.

 

Yes, sounds the same no matter what rpm. I have tried putting it in neutral and coasting down and you can still hear it. I don't think it would be the tires. Put a bigger set on it a few months back and it still did it with both sets of tires. But I will look into the wheel bearings!

 

Answer the phone.

 

I would if I could find it lol