Have owned an '02 TL since almost new. Now has 178k. Michelin stock tires have about 20K on them. Over the course of the past 5K have begun to notice a "hum" type of road noise at all speeds. Neglected to have tires rotated for about 9K. Did so about 500 miles ago. Some cupping was noticed. Am guessing this is the cause of the road noise but expected it to diminish by now. Any thoughts?

 

If the tires were causing the HUM you would have noticed a change (for better or worse) when you rotated the tires.

Run your hand over the tire treads. If it feels "rougher" in one direction or the other, swap sides on the worst two tires. (NOT front to back, just side-to-side)

If you ARE having a feathered tire issue, it will take a lot more than 500 miles to even out the tread...more like 5000 miles!

 

If the tires are actually cupped- the shocks/strut assembly is worn out

ck it for oil leak traces on the main body

 

Bad wheel bearings go "Whooooooooo"

 

wheel bearing.