Can someone confirm worn out tire "general noise" for me?

[goblues38]

My factory K02s have 41,*** miles and I rotate them every 5-8k miles on a 5 tire strategy.

Took a road trip this weekend and did 400 miles each way on the highway. I get a LOUD rhythmic noise or whirring at speeds of 60-90. goes away after 90. speeds up / gets louder as I speed up. Can feel a slight vibration in the steering wheel as this is going on. Reduced the rear tires by 4 psi and it seems to make it a little quieter.

Does not change if I am on throttle vs off throttle so I am pretty sure it is not drive line slack.

Does chase when I hit dips at speed on the highway.

I suspect, it is just my tires are at the point where I need to replace them, but just want to make sure I dont have something like a bearing issue in a hub or something.

 

[smurfslayer]

I’ll bet the stick is significantly degraded on those KO2’s. Mine had some tread left but the heat cycling had caused grip to degrade significantly at 36-40k. I swapped them out at ~41 - 42k to a new set of KO2’s. Traction, handling, compliance road noise all significantly improved.

You’ve probably notice they make more noise immediately after rotation. That will even out for the first few rotations but my last rotation in the 30k range the noise didn’t go down or increase, it stayed basically the same.

Your KO2’s are shagged. Get new hoops.

 

[NHbeast]

I have 32k on a five tire rotation. Rotate every 5k at oil change. Same rhythmic noise. Looks like another 10k plus to the wear bars. Doesn't look like they will make it to 50k. :-(

 

[stevenstommyboy1]

My last set of KO2s were cupping by that mileage and had the same sound. Rotated every 5k. That’s why I got a set of Falken AT3Ws. So far so good and cheaper.

 

[goblues38]

thanks all for the replies

 

[Retired in TN]

Any vibration that lights up and goes away with increasing speed is a tire harmonic, most likely a first order harmonic (occurs once per tire revolution). These tire harmonics transmit the worst when the tire revs/second matches the natural frequency of the suspension. Mostly these overlap at highway speeds. Change the spring rates, tire stiffness, vehicle load, etc., and the natural frequency changes. The key is that unlike tire/wheel imbalance, tire harmonics do not change magnitude much with vehicle speed.

 

[nikhsub1]

The KO2's are ******* garbage. Mine got loud at 15k miles, I chucked them as not only were they loud, on road and wet traction was the worst I've ever experienced. I guess consider yourself lucky (or dumb ) for getting 41k miles out of them. I went with the Cooper AT3 XLTs and could not be happier. They put the KO2s to absolute shame. And they are lighter, and E rated.

 

[isis]

Mine get a 4-wheel rotation and are getting loud at 31k. I noticed they’re more squirmy in rain than they used to be too. I’m getting new ones before winter. They’re somewhere around 5-7/32nds

 

[smurfslayer]

Mine get a 4-wheel rotation and are getting loud at 31k. I noticed they’re more squirmy in rain than they used to be too. I’m getting new ones before winter. They’re somewhere around 5-7/32nds

That’s about when I started noticing part throttle traction falling off. Still adequate tread and passable off road as a result. You’re correct though, pitch ‘em before the first potential snow. Which in PA is ... what, September?

 

[isis]

That’s about when I started noticing part throttle traction falling off. Still adequate tread and passable off road as a result. You’re correct though, pitch ‘em before the first potential snow. Which in PA is ... what, September?

Hopefully not but who knows anymore. It hit almost 90 in mid April and then snowed two days in mid May. The whole seasons changing seems to oscillate pretty good during transitions.