so my ap2 has 1600 miles; picked it up 2 weeks ago with only 6 miles. i was the only one that ever drove it...no burn outs, no donuts or launches.

whenever i'm cruising in 5th or 6th gear at exactly 55-58mph at around 4000-4500 rpms...theres a lowpitched whistling being emitted from the rear. when the car is stationary and i bring the revs up...theres no noise; which makes me to believe its coming from the differential at that speed (55-58mph)regardless of which gear im at...however heres the kicker...it only makes that noise when im gassing it...which also leaves me to conclude it can be just exhaust noise...

ive taken it to 2 dealers...one says its the diff...the other says its just exhaust noise.

-sigh-

some feedback from you guys would be helpful...billman?

-a

 

I had 6 miles on mine too Congrats!

Did the same whine noise in the rear left but mostly at around 68~72mph. It was constant on that speed and not dependent on the throttle. I got it checked out and they said it was resonance from the underbody. Put a different exhaust on and it indeed went away.

I'm guessing give it some more time and if it gets worse, take it in for a checkup. You have nothing to lose if they need to swap out your diff now or in 5k miles.

 

I have faint gear whine around the same speed that you are describing too. I can't hear it all the time though. The top has to be up and the windows closed. The atmospherics have to be just right too (cloudy, low pressure), attenuating every mechanical sound that is going on in the car. But there is one difference, I only hear it when I am lightly using the throttle and have just let off on it. You say it only happens when you add throttle.
One thing that I have never figured out is how after market gear companies give you a specific heat cycle regimen and fluid change to follow while breaking in your new gears, yet Honda never mentions it in the owners manual for the break in period procedures.
If you want a recommendation, I'd say drain the diff fluid out of there soon and fill with fresh fluid. I see that Rick's Accessories (site sponsor) is sellling LE 1605 now. That would be a great choice.
One other thought...our S2000's make lots of wonderful noises, especially with the top up. Try not to become a hypochondriac!

 

In your other thread about this you mentioned the dealer changed diff oil.
You never posted what oil they used.
You said: They used what Honda recommends (I'll bet you they used 75W-90 oil).
Honda recommends a straight SAE 90 GL-5 oil.
(old spec ( long story) but LE-1605 fits that spec too)
Confirm that by reading your owners manual
(that may be hidden in the secret compartment )
The metal flakes you mentioned is most likely from brake-in => normal.
But.. without pics its a guess.

INDYMAC Posted on Oct 25 2007, 11:58 AM

Ask an owner you trust in your local forum to have a listen.

With the LE-1605 in the diff you can't go wrong.

 

I had this problem with my 05 where it was rather noticeable and had my car into the dealer numerous times, including different dealers. After taking a hiatus from owning an S, I recently picked up a new 06. I seem to have the same faint whine between 56-59mph again, although a lot less noticeable.

I swapped out the factory fill for Mobil 75W-90 at 3500ish miles, with no significant change in regards to audible noise at that speed range. I'll be changing to LE-1605 on the next go around, per SpitfireS and other folks' suggestions and real 90w spec. For myself at least given my experience, I'm slightly less inclined to be worrisome for now.

However, I'll let the experts chime in