High pitched harmonic at low speeds, any clues?
 

The car is a month old. Since I've owned it, the car has made an odd harmonic at very low speeds. Typically, 2nd and 3rd gear do this in the 4000rpm range (normal road cruising). The harmonic soundslike a wheel bearing does when it starts to go. It's a higher pitched, drawn out sound that resonates in the car, and goes away when I slow down or speed up. No issues at faster speeds.

It ALMOST feels like something is rubbing since I can feel it in the steering wheel... but nothing is. I've checked under the car and looked at all the wheels / busings / connectors. I'm taking it in to the dealer this week for an oil change and I was going to mention it to them, but I wondered if anyone on here has had a similar experience.

Thanks for any info people.

-Ninja

I bump, therefore I am.

Check tire balance? Rim out-of-round? Tires showing wear (espacially uneven wear or cupping)?

I've noticed a very faint, intermittant harmonic that seems to be coming from either the driveline or rear-end. So far I haven't been able to correllate it with particular speeds or engine rpms, but it does seem to be independant of road surface. My car is 5 months old.

I haven't excluded paranoia.

I had a singing differential in a previous car, this isn't really like that- but who knows?

YES! Whatever you have, I have. Same exact description.

Originally, I thought it to be the type of road surface on my street ( more granular pavement VS black top ), then I thought it was the tires... but if it were directly linked to something in the car that moves, then it should get louder or higher pitched as the car goes faster or slower.

one of the more noticeable signature sounds of the renensis rotary engine is a high-pitched harmonic. you will hear it when the engine idles as well- some days more than others, as it's not always consistent. initially, i was intrigued by this as well and searched the forum to learn that it's perfectly normal. search is your friend :)

Good to know Detrich, but this sound is definitely coming from the rear of the car. I know about the whirring sound of the rotary engine and yes, it is very distinct. The sound I am referring to is in no way related to the engine so far as I can tell.

While I searched various ways using multiple keywords including "harmonic" "high-pitched hum" etc, it turned up no relevant info. My apologies if this has been brought up extensively before.

it is a possibilty that the drivetrain brace/torque arm/whatever you want to call it was not installed properly at assembly. it runs from the back of the trans to the differential. if it is not secured in the correct area it can change the pinion angle enough to cause the trans to get in a bind and you will get a noise from it. the same goes for a miata, its got the same setup.

its the only thing that immediately jumps in my brain

Harmonic Noise @ 43 mph
 

I'm new to this message board thing, but my wife and I are experiencing the same harmonic type of whining in our 2004 RX8. I don't drive it that often but enough to know that it hadn't made this noise before now. It's definitely coming from the rear of the car and consistently at 43 mph. I tried in gear up through 43 and down through 43 and then neutral down through 43. Every time it approached 43 mph the whining would slowly become more pronounced, peak at 43 and fade. Maintaining a speed of 43 the whining remained constant and very annoying. Its at the dealer today and they seem to think its the tires? Something about "cupped" tires makingthe noise. This doesn't sound right to me - any thoughts?

Dude I am experiencing the same thing! Did anyone on here ever figure it out? This thread just died and never came back.
We'll hopefully someone will know what the answer is to this same problem I am having. Except I caused it. I just don't know how to fix it. I was jacking up my car from the diff. Heard a noise I could only describe as metal bing. And after I was finished with my work I went for a test drive. I started experiencing these exact same issues you just described. Any help?