Subaru Problems? Ask a Mechanic for Answers ASAP
Was the tire shop (or wherever the wheels were balanced) able to check for a bent rim?
The Tribeca is pretty solid in the suspension, so it's not likely that something other than a rim could have bent unless it was a really hard hit.
Is there a grumbling noise as well?
It's possible, but not likely. An alignment would have shown a bent suspension part, and bending an axle on this vehicle is not possible without bending suspension parts first. That's the whole idea behind independent suspension.
I would have a different tire shop check the wheels and tires.
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