I have a very noticeable clunking noise coming from the back of my car. I jacked it up and checked my axles, all fine. then I spun each wheel both directions, when I spun them the other wheel spun in the same direction with no grinding. I did get a small clunk when I started to spin the tire but it only sounded like a little shaft play when I changed directions. I hear the noise mainly off throttle and I hear it most easily when I slowing down to stop. I also hear some whining but that may just be my walbro fuel pump.

 

I just went outside to try spinning them again. this time for a longer period of time, after a few full rotations the opposite tire stopped spinning for about one rotation and then continued spinning in the same direction.

 

Odd, normally when you spin one tire, the other goes in the opposite direction. Your LSD may be crappola. What kind of fluid you been using?

 

I have honda fluid in it. but it is 1 year old and 27 thousand on it.

 

any onther thoughts???
Im gonna change the fluid today so I guess well see what happens.

 

Honda fluid in the diff? I didn't know they made a SAE 90W GL-5 gear lube for our car. I suspect that this could be the culprit.

 

This is the primary reason why I asked. Specifics would have been nice. "Honda" automobile division does NOT have an in house diff fluid for the S2000. They must get it from the aftermarket or from Honda "motorcycle" division. If you have "Honda" diff fluid in your car, you have the WRONG fluid in it.

 

I would leave the fluid in the car, take your receipt and car (via flatbed) to Honda and let them investigate what's going on.

 

If you throw away the evidence, you got nothin'.

 

Prominent clunking sounds after letting off the gas pedal after moderate acceleration is a good indicator you have rear differential problems, though not absolute. Take it to Honda and hopefully they put the last oil in there and not you.