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Tires rumble and shake with sharp u turns

Have a Subaru AWD. Tires will rumble when i make a very tight turn. Not every time. Told it could be transfer solenoid, but have also heard its normal.Fairly expensive to fix, but told it could damage transmission if left alone. Anyone know about this?

This is likely to be a severe case of “torque bind”, and is probably the result of having caused damage to the Viscous Coupling by running the car with mis-matched tires. Have your mechanic check the viscous coupling.

I presume automatic given solenoid.

Are your four tires matched not only in brand/model/size but tread depth? If not get a matching set on the car. Also make sure air pressure is set properly if tires are matched.

Looks like the problem had something to do with the TBS. I think the # was low. It was a quick fix and cost me $15.00. The car runs much better and the rumble is gone for now.

Thanks

TBS?

The Turner Broadcasting System?

Huh?

Subarus with automatic transmissions have an AWD transfer valve and clutch pack in the rear of the transmission. When the transfer valve wears, either through normal wear or when mismatched tires are fitted, the clutch pack does not release when it should, binding the front and rear axles together and making the rumble and shake you’ve described.

YES, it will cause internal transmission damage if allowed to continue.

In the short term, inserting a fuse in the FWD receptacle under the hood should disengage the clutch pack and the rear drive, thus eliminating the binding.

Long term, the valve and clutch pack will have to be replaced. I paid around $750 when my Legacy needed this repair a few years ago. You’ll want to find someone familiar with Subarus for this.

If your car has a manual transmission, which uses a different AWD system, a change of transmission oil might help.

No, supposedly it was the TBS that was the problem.

I still think that my theory and your theory are correct, but we will have to wait for the OP to let us know if this $15 fix was the real solution.

I missed the dates. I didn’t realize how old this was.

What’s a TBS?

That’s what I am wondering.
Maybe I am ill-informed, but the only thing I know of with those initials is Turner Broadcasting System.

Whatever it is, supposedly it only cost the OP $15, and it resolved the problem.
Truthfully, I am skeptical.
Other than a PCV valve, I can’t think of any parts that would be so cheap.