you might want to try going a little over the speed you experience the sound at and just putting the car in neutral and coasting down and try to see if the noise becomes apparent when you're at the speed it does it at. that would get rid of the chance that it's the intake howl and if you still hear it then it would probably still be something drivetrain related.

 

I've had the same type of faint whine in my 06 since I've had it(4-26k miles). I've had LE607 in the diff most of the time, and now LE1605. I can only hear it at 60-65 mph, mostly in 5th gear.

 

Well I took the service manager and a tech out for a little spin yesterday. The service manager didn't seem to think there was anything wrong but he admitted that he didn't know much about S2000s. The Tech on the other hand heard the whine and told me that it wasn't normal. They are going to be tearing into the diff this afternoon. I'll let you guys know how it turns out.

Kind of funny... I found out this morning when I dropped the keys off at the service desk that a different customer's S2000 was getting the differential replaced today.

 

it's the same story as the trans: most people never bother to change out the fluid, or if they do, they wait too long

the key is regular maintenace, it's less important what oil you use

 

The service manager just called to inform me that they will be replacing the differential. He said that they took it out for a long drive with a set of "road ears" and that it deffinately needed to be replaced. I was pretty surprised. Next week I get my new differential!

 

wow, Honda takes care of their owners I guess....someone else forgot to install the oil pan plug and got a new engine