Tires: Tire noise most noticeable at speeds over 40mph, 2005 toyota avalon, wheel bearings

Question
QUESTION: Hi, like many other who have asked you this question before, over and over, I am here to ask you yet again. As i am not convinced by the answer and my problem might be a little different.

I own a 2005 Toyota Avalon Limited i bought it used recently with around 37000 miles on it. The tires are just about worn out(still have a few 100 miles left in them). The problem is that when i drive i hear humming/buzzing noise coming from the drivers side(either the front or rear can't really tell). The noise is accompanied by very little vibration. Also the car pulls to the left.
Now i took it to my local tire shop and had alignment done and all four tires rotated in an effort to identify the problem. Well the alignment is still out and the noise is still there. The noise did not shift and still comes from the driver's side. I took it back again to the same guys telling them the alignment was still out and pointed out the humming sound. I also told him that when i turn the car to the right the noise gets louder and when i turn to the left the noise gets softer/decreases and told him it might be one of the wheel bearings. They further adjusted the alignment a little more, and told me that there is no physical indication of a worn out wheel bearing as when the wheels were jerked and spun while on the life they made no noise and wouldn't budge. But the tire shop guy kept insisting that it is the tires as they are about to get worn out.
Now, I have no problem with replacing the tires but i am not totally convinced its the tires as when they were rotated the noise did not shift, they also do not have any uneven tread wear. But I am baffled as to what is the cause. Do you really think it is the tires? and do u think once I replace all 4 it will be fixed? Also another person from an online forum suggested it might be a seized/sticky brake caliper, but the noise does not increase or decrease when i brake(actually it decreases when i brake due to the fact that my speed is being lowered not because i am pressing the brakes). I also had a break check when i took the car in for alignment and the breaks have adequate life left in them and i was not told of any sticky calipers.

Please Help
Thanx
Haris

ANSWER: Haris,

Aligning the vehicle only solves the source of the problem, and not the problem itself.  The tire still has a wear pattern on it that causes a pull and a noise.

I'll bet they did not rotate the tires.  That would explain why you seem to have no change.  But without replacing the tires - and you've said you need to do that anyway - there is no way you can be sure, unless you are willing to go and do the work yourself.

And from what you have told me, I can think of no other explanation that fits the facts.

---------- FOLLOW-UP ----------

QUESTION: Hi, like you and many others i am a very skeptical consumer, so when i took the car in for alignment, and when i parked the car at the shop i removed the caps from the valve stems from the driver rear and passenger front tire. After the alleged rotation and alignment. I noticed that the tires were in defferent positions. Now it might be the case that someone saw me doing this and changed the caps, but i higly doubt it. But 90% i think they did rotate the tires. Any other suggestions would help.

Thanx.

Answer
Haris,

Thanks for the additional info.

I still think you have not solved the problem, in that the tires - what is causing the pull and the noise - are still on the car - and probably on the same side.

Nevertheless, you still have a need for new tires, so that is the obvious next step.

Should that not solve the problem, then I would suggest you have the front tires swapped side to side - to verify it is not the tires causing the pull - and if it doesn't change anything, then the vehicle is still out of alignment.

As far as the noise is concerned:  If changing tires doesn't fix the problem, then this is going to be something you will have to work through with a vehicle dealer.  Noise can be very difficult to fix, but I'm still of the opinion that changing tires is going to fix everything.