I heard a loud whining noise from the rearend of the car while driving today. It happened at about 40mph coasting. I did not have my foot on the gas. I heard the noise and threw the automatic transmission into neutral and it seemed to stop. Is this a torque tube problem or transmission? How can I pin point what it is?

Thanks

 

I went out in the car again to try and test the problem. My first thought of the whine stopping when putting it in neutral was a coincidence. It is still whining even in neutral. It does seem like it only does it in the 40-50mph range. Any faster and it doesn't whine. So what is it, torque tube, transmission, or wheel bearings?

 

Mike,
No good idea as to what is responsible, but two thoughts come to mind: Put the rear up on jack stands (front wheels securely blocked), and
- check the xmission and diff fluid levels - edit iodiotic omission - car to be leveled for correct fluid checks!
- start the car and place in gear. stethoscope every part of the drive train. Torque tube/convertor/xmission/CVs/hubs/etc. If nothing shows, get someone in the car to bring the speed up to ~40 MPH.
This could give you some facts to work with.

 

Get up to ~60 and shut off the motor. If it still whines you have eliminated the torque tube. If it doesn't, check your front pinch bolt. Actually, check your front pinch bolt anyway. Unless you just did it, it's probably time to do TBF prevention.

 

I already checked the pinch bolt and relieved the pressure. What are the first signs of the torque tube going out versus a wheel bearing or transmission? I a whining or howling all linked to these three parts?

 

Read up on the good material on torque tubes by Nichols/Pirtle/etc. Bearing noises travel beautifully through the chassis to mask their source - and each one often sounds differently when failing, car to car; therefore, unless one has a tremendous experience, it is difficult to pinpoint the particular bearing.
Dave's test sounds good to stop rotation of the TT - and the front half of the convetor: by shifting to neutral, the only loaded bearings will be the diff, CVs, and hubs.
I'd still check fluids first - for the $$$ one's are bathed in those fluids..