When I hit speeds over 70 mph, a very noticeable high pitched frequency hum kicks in. It sounds like something which would be coming out of a speaker, and not at all like some body part vibration. Anyone else notice this? It's borderline annoying, and one of those things which could be tough to troubleshoot. I can hear myself at the dealership- "It's fine until speeds over 75 mph. Can you find the problem?" Could be a bit tough :???:

 

Is it there with high rpms at lower speeds?

 

I've noticed that sometimes the electric steering pump whine becomes more noticeable at high speed cruising, and although I wouldn't quite call it annoying, this may be what you're hearing.

 

mckinneymini- no, it only kicks in at high speed, and it stays there until the speed drops down below 70 mph again. The rpms don't seem at all related. The thing that makes it strange is that it doesn't sound at all mechanical, it sounds like electronics- a really high pitched speaker hum- and it sounds like it's behind me somewhere in the cabin. It happens whether or not the radio or the ACC is on- so it doesn't seem to be related to either of these. Again, anybody have any ideas?

 

Since it is not RPM related I would lean towards the tire tread as being the culprit. I would look for changes in pavement ie: from concrete to blacktop and see if the change in surface causes a change in the sound of the hum.....just a thought, new tires sometime put out a pretty good hum until they wear in.

 

No hy speed humm, but at 115 mph, I get a massive rush of air around driver side door. Passenger side ok according to passenger. I smell a recall...

 

Absolutely not tire noise- doesn't sound like it's being physically caused in any way. It sounds like when you have a car radio that isn't properely shielded from rest of the electrical system and you can here the high pitch hum speeding up or slowing down w/ the alternator or generator, only this is very, very high (one frequency) and again, only at high speeds.

 

Do you haveany aftermarket items on the car? Had a radio/amp installed? GPS? Alarm system?

 

Is it coming from the back? Could it be a ABS wheel sensor? I have had some success with othe vehicles giving a sober friend a stehoscope and pressed against various interior panels.

I can tell you its is the most difficult stuff to track, but the most rewarding when you trackj down that little bugger.

Let us know whet you try/find out. :smile:

 

Hard to locate, since it's so high pitched, it's not really easy to check directionality. I DO have an aftermarket car alarm installed, and it functions perfectly- it's always on when the car is locked. I suppose I could try getting it up to 75 mph or more w/ the car doors unlocked. We'll see.