i have a small bit more driveline noise (still performs just fine) running M1 75w90...after about 10k miles on this gear oil i decided to try out Amsoil sg 75w110.

hope it quiets up a bit.

 

All Amsoil. Signature series synthetic motor oil has low volatility. Synchromesh tranny fluid is good replacement for Honda MTF. Extreme pressure 75-110 diff gear is good for temperature extremes.

 

The factory put straight 90w in the differential when new. The nearest to factory spec is LE 1605 or a 75/110
For added protection and better performance from the LSD use a 75/140 There is no disadvantage to using the 75/140 at all Amsoil, Mobil1, LE-1605, and Motul are some of the best on the market.

If any of you run a aftermarket clutch type LSD in the rear use the Motul 75/140 this oil is by far the very best I have used for clutch type LSD units

 

Kiss your transmission goodbye if you go that long between services. Trans fluid will get pretty beat up in 20k miles on a track car.

30k is the perfect mileage to do both under normal driving.

Trans fluid and dif fluid are not affected by time (unless its extended years) so doing them seasonally is a waste of time and money. Mileage is key.

 

I just do diff yearly trans once every other year, I put about 12-14k miles/yr, no problems so far after 132k mi.

 

Wanted to run LE1605;ordered it from Rick's,but could not deliver,because HazMat...
Back to Amsoil 75-140.

 

Diff fluid is 90W single grade.

Honda doesn't sell this anymore, just like pretty much every one else. It's all multigrade these days.

I found a agricultural vehicle / lorry garage that still uses 90w for some weird machines. They sold me 2 L for 5 bucks or so. That's your best shot I think

 

I recently had a service done at a Honda dealer and they used:

Genuine Honda 08200-9014 Hypoid Gear Oil Hgo-1 Gl-5 75W-85

Any thoughts about using this product...

 

You used this is the differential? Isn't this transfer case fluid?

 

You should be able to feel or hear when the transmission fluid needs to be changed. Especially in my RSX-S, the transmission gets noticeably notchier, and may grind into 3rd gear after several thousand miles. Changing fluid fixes it. I have heard that the long molecules in the lubricant can be cut by the gears (shear forces) and lose some of their lubrication properties.

The S2000 is a great, and valuable, car. Protect your investment. At least once per year. If you race, the higher temperatures also break down fluids, so racers typically change fluids after every race -- including brake fluid.

Don't neglect your hydraulic fluids and coolant.