Hi All, I've got a situation with a local shop that isn't passing the smell test. Our 98 V70 AWD is making a constant, higher-pitch grinding noise when rolling. Sounds a lot like when you're metal on metal with the brakes. I took it to an Euro import shop that I've never used before and they diagnosed it as:

"The torque tube bearing is failing. $350 to replace the bearing - if it can be replaced independently - $525 if not and the entire unit needs replacing."

I'm far from a mechanic, I basically know just enough to be dangerous. But I have never heard of a torque tube. Is this for real? Or maybe Volvo has a different name for a relatively common part? Or maybe I'm being flim-flammed? Any clues?

thx!

 

Never heard of it, may be referencing something else, sounds like something in the AWD.

Have them point it out.

 

 

That sounds believable to me, but the term "torque tube" is of course wrong. I assume they are talking about the bearing in the middle of the driveshaft going to the rear wheels. I could believe that is the problem. I could believe that it's unserviceable, The driveshaft is going to cost more than $575 from volvo if it's unserviceable, but it's not much labor to install. There are some threads here and there in forums by people who replaced parts of them in a way that Volvo didn't intend.

 

For the more academic question, "torque Tube" was a form of rear drive that used a stationary tube concentric around the driveshaft that was rigidly mounted to the solid rear axle. It did not turn. For context, this is how Chevrolets were made in the 1930's. This tube gave you a huge torque arm on the rear axle, so you never had to worry about rear axle control or "wheel hop". It stayed put. There was no rear u-joint as the tube and driveshaft were both dead straight. GM abandoned it in 1955. I figure you've just run into somebody that refers to a supported driveshaft bearing as a "torque tube bearing". I could be wrong.

 

yes the term was commonly used with Corvettes (sigh...). I'm curious if they were referring to the propeller shaft center bearing. Note that the drive shaft between the transfer case and the rear differential is held up to the floor pan by a center bearing which can cause noises.

 

We'll probably never know since this thread is 8 years old...

 

good thing too, I haven't worked on a Corvette in about 35 years :-)