I have a 2001 Ls 430 with around 112,000 miles on it. Over the past month or so I have been hearing a strange sound when driving. The sound is kind of like a dog whistle and seems to be coming from somewhere in the front of the car, possibly the right side. The sound only happens when driving around 38 mph - 45 mph. The sound is loudest at around 40 - 42. The sound is not as loud but you can still hear it when going anything above or below 40 mph to 42 mph. I have tried turning off the AC and radio but the sound is still there. It also only happens if I'm driving after the car has sat for a few hours.

 

Is this with winter tires, or summer / all-seasons?

 

All season tires. I was looking at other threads and some say that it has to do with fan motor or AC but I have turned my AC off when driving but this still happens. I had my AC filter changed before winter but every now and again when starting up the car I get the AC filter warning saying that it still needs to be changed. I think the cold weather may be a factor in the sound. But again the sound only happens if the car has been sitting for some hours and have to be driving at around 40 mph.

 

Have the same issue... It does only seem to present itself during the winter months. I'm on Michelin mxv4 in case anyone wonders. Very faint, but strange dull whistling sound that seems to fluctuate in pitch (based on speed) during that speed range mentioned above. Hmmmm.....anyone?

 

Wheel bearing starting to fail?? I would think that would be more of a rumble or lower pitched hum, though..

Check the lower engine cover and make sure all the hardware is securing the cover to the mounting points. You could have a loose corner that is being forced down while driving and causing the wind noise you're hearing..


Just a thought..

 

I'm guessing neither of those, only because it happens during COLD temps. I've had mine during 4 winter seasons and it never fails. I don't think it's anything to be concerned about, but damn curious for a logical explanation.

 

Possibly servos or something electrical in the dash

 

Thanks I will look into that. I live by chicago so the weather is always switching up. During warm days in the 70's I did not hear the sound but when the temp dropped the sound reappeared. And like I said its only at 40 mph and if the car has been sitting for some hours. I have 113k miles if that matter. But I will look into the servos or dash.