Hi all...I'm new here...been lurking and reading for a long time but never signed up.

But I have a question that maybe someone can help me with.

I have a 2007 MT RX-8...have had it for about a year...I have no problems with it except for one little annoying one that I hope isn't a bigger issue.

I don't drive that often on the highway, but if I do drive at highway speeds for longer than around 30 minutes I have an odd problem. Once I get off the highway after driving for more than 30 minutes or so, I get an odd noise the first couple times I am starting from a stop in first gear. If I had to guess...I would say it is coming from the front wheel well area. And if I had to try to describe it...I would say it is a non-metalic grinding noise. The first time I heard it, I honestly thought it was my tires "sticking" to the asphalt. It is an odd noise...not one I have heard in any other car. I asked my wife to describe the noise...she said rumbling. You can also kind of "feel" it...but very faintly.

The noise completely dissapears after I stop/start a couple times off the highway. There is no smell assoicated, no power loss, no hesitation...just the noise.


Does anyone have any idea what this could be or have had similar issues?

 

check your wheel lug nuts are tight enough torque them to 108 ftlbs.

 

Next time the noise arises, try and get to an open space where you can do some "figure 8" patterns. If the noise gets louder when you are turning, it may be a rear wheel bearing going bad and it will be the wheel on the outside of the turning radius.

If you have more than 50K miles on the car, also take a look at your tire wear pattern. If the tread blocks have become "feathered", you may have bad dampers (shocks) and that will result in a little bit of tire rumble noise which may not be noticeable at highway speeds but moreso at slower speeds. Also check your tire inflation pressures.

Although the lug nuts are also a good place to start, they usually result in a "clicking/clunking" noise if they loosen a bit.

 

Thanks for the suggestions. I will check the lugnuts and try to do some figure 8's next time it happens.

But thinking about it now I do think it happened more when I would turn after getting off the highway. But only in 1st gear (maybe second) and only for a the first few times after getting off the highway.

 

it may have more to do with speed...like, not related to starting or 1st gear or 2nd gear, but simply that by the time you're in 3rd and up you're doing 40mph and up and you can no longer hear the noise, especially at highway speeds. i'd do the lugs b/c that's easy, but then do what charles suggested...drive around in a parking lot trying different things, turning, etc., to really try to pinpoint WHERE it's coming from and what makes it louder/softer or start/go away

 

I have had this problem as well. Does the sound go away when you turn off cruise control? After you park the car and restart it? I had the same thing happen Sunday. (It had happened previously as well)
I parked and asked my friend to drive it around and tell me if he noticed anything. The sound and feeling had vanished. It feels and sounds like the tire is rubbing on the fender but I have checked that before. It is tire/wheel independent. I just switched to 17" winter tires from my stock 18s. I generally don't drive on the highway often but it has happened every time I take a long trip. I will have an opportunity to test it again Wednesday and can let you know what I find.

 

Just got to preform another test.

After 80 Miles around 73mph average speed.

Didn't notice it after stopping at stop lights after highway.
Parked car.
10 minute wait.
Started and headed back out. Noticed slight noise and "rubbing". Checked lugs, tires, and wheels. Nothing seemed out of place.

It seems to be more severe after longer distances. Like its a function of miles traveled or total heat etc... Could it be some sort of belt issue? Something "slipping".

I have autocrossed on the weekends and this problem never occurs. I also never notice it in town while driving only after extended trips at high speeds.

Can an admin also move this to the troubleshooting section for Series 1.

Thanks for the help everyone.

 

Check to be sure the rubber wheelwell access flaps are still properly pinned in-place (?).

 

Hmm. Check those too. OP you have any updates with things you have tested?

 

This sound you speak of...

how loud is it? can you record it?
is it constant or does it vary with speed or rpm?
is it more of a constant hum or does it have breaks in it?

 

yup we need more info on this sound some specifics too

 

Thanks all. I will try to record it later today after my drive back to Champaign.

 

Updated for those that have been following this will similar problems.
Getting mine checked out next week. If it is the diff is should be covered under
http://www.coremazda.com/tsb/rx8/pow...-extension.pdf

I will let you know the results.

https://www.rx8club.com/showthread.p...16#post3834216