Just got back from a long cross country trip (PHX to Michigan) and the tires developed a growling noise during day 2 of the trip that stayed with us for the whole 4 day trip and beyond. During a dealer inspection in Traverse city, they said the tires were "feathering" and it needed a 4 wheel alignment.
I didn't know what feathering meant - had to look it up on-line. Checked the tires myself and there was no feathering (inside to outside cupping), just a slight bit of regular cupping on the very outside tread blocks on all 4 tires.
Now "4 wheel alignment"??? are the rear wheels adjustable? I didn't think they were? So it would really be just a 2 wheel alignment.
Decided against that - seems like the dealer was just trying to scare me into spending money.

So while I had the front left wheel off to fix the ABS (a real problem), I looked at all the tires again and decided they may be underinflated. So I pumped them all to 37psi instead of 35psi (on my gauge) for the return trip and that did seem to reduce the noise by half for the return trip.

I have done a corner to corner tire rotation, now that I'm home again and will run it for a bit to see if the noise (and slight tire cupping) goes away.
The tires are at about half life (30K out of 65K miles on them) They all seem round, no eggs or obvious damage.
The rear axles turn nicely, no apparent problems there. The shocks work well, no bouncing after loading them up.

The only thing I'm thinking could be happening is that the rubber spring seats on the front shocks could be flattened out and have adjusted the alignment a bit.
This issue has not shown up before, wonder what it is???

Opinions??

 

If tires are cupping then you need new shocks.

If the tread looks like sandpaper you need to have your toe adjusted.

If the inner or outer edge of the tread is worn more than the rest you need a camber adjustment.

If the center is worn more than the sides you need to lower your psi, increase psi if both edges are worn more than the center. (look at wear bars for this)

Sounds to me like you need new shocks. The noise could just be from those tires on a different road than you're used to. Cupping is always from blown shocks though.

 

Tread was smooth, not sand papery.
The inside and outside did seem to be a bit lower than the middle blocks, which led me to add a couple of PSI to the tires.
Some of the roads were awful, specially where the tarmac had been chained off in the road works areas. I suspect if the XB had more sound deadening, like the newer cars do, I would not have heard the noise on the way back after adding a couple of PSI.
I think the shocks are OK - If I pop the rear hatch and sit in the back then jump out, the car just rises with no overshoot. Bouncing on the front gives the same result each side. There are no oil leaks around the shock shafts either.

Thanks for the reply though

 

So I finally got around to taking the car in for an alignment check and YES it was off. How much off? They wouldn't tell me, but they did correct it and it drives much straighter now and is not so sensitive to the road surface.
The tire noise is reduced also. I suspect in the next 1000 miles or so, the noise will go away.

Bad news? When they (Gunnells, Mesa) were backing the xB out of the bay they hit another car that was being backed out at the same time. That put a nice dent and tear in the bumper cover
Good news is they fessed up and got it handled at a local body shop (LP's Mesa), just some added inconvenience for me, but as I'm retired, not much of an issue.
That also got rid of some scratches I had on the top surface of the bumper after people had dragged stuff out of the trunk instead of lifting it out.

So all in all, probably a plus experience, but it reminds me of why I don't like taking my car to a garage, Toyota or otherwise
Probably just the control freak in me

 

why couldnt they tell you how much the alignment was off? every time I've gotten an alignment done on any of my cars I've received a print out of before/after.

 

That I don't know. I was expecting a printout showing the before and after, but they gave me nothing. I asked the boss guy and he gave no answer, except it was "a lot".
Sort of reminds me of going in to see doctors...