02 Honda Civic SiR with Goodyear Eagle Sport All Season tires.
I've been getting a humming noise at about 40km/h and higher. I changed over from winter tires about a month ago, but I can't recall whether the noise was present before that.
- starts at about 40km/h and is present at any higher speed
- constant pitch (does not follow road speed)
- volume is nearly constant, maybe a little louder with increased road speed
- present in and out of gear, clutch in or out
- turning left or right does not change or affect the noise
- no vibrations anywhere while coasting, accelerating, braking, or turning
- car tracks perfectly straight while coasting, accelerating, and braking
- tire ages range from 3-4 years
- tread on the same tire ranges from 8/32 to 10/32 (edge tread vs middle tread). Is this normal? I check my tire pressures regularly to keep them correctly inflated, but I can't speak for the previous owner.
It's difficult to get a good recording of it. I would describe his a mid-pitch hum (edit: I can tell you the tone is one B above middle C :) and not the typical low rumbling/growling I often hear described as wheel bearing failure.