my mechanic just recently switched me to Motul 0w40. The clutch also needs to be changed soon and thus needs new gear oil afterwards, and he would like to to 100% motul across my car. What would you guys recomend for the trany, from motul (or not from motul) as well for the diff?

 

There is an excellent FAQ at the top of this forum called "The Oil Journals". I suggest that you read that first.

Two Point:
1. 0W 30 oil is not recommended in the F20C or F22C, at least it isn't in North America.
2. The clutch in the S2000 is a dry plate clutch and changing it has nothing to do with servicing the transmission fluid.

 

were going to be changing it anyways,

ow30 isnt but what about ow40 then?

 

10W30 is recommended. 5W40 is listed as an alternate. Engine oil, that is.

 

I searched the link you gave me but yet no answer on to 0W40. Why is it not good for the s2000 (im looking for whats good for the street and what is good for the track)

as for diff and trany I have my answer, but engine oil still lost. not to mention I am 100% lost as to the whole differences behind each oil weight and grade

 

It is not "just" the viscosity range 10W-30 or 5W-40 that is recommended.
Also it needs to meet a minimum quality spec.
Being API SG, SH or SJ.
(according to my MY 00 German manual)

I don't know the API rating of the Motul 0W-40, but if it meets (or exceeds it) API SJ you are fine (IMO) with that viscosity, especially if it is a synthetic (most likely).

Thoughts behind it is that a wide viscosity range oil is more likely to "shear down" to a lower viscosity. The higher the quality (API) the less it will do that.

The viscosity @ operaing temp is 40 so that is no problem whatsoever.
At a cold start is is nice and thin (0W) and flows nice and fast to where you want it during the first cold running seconds.

 

Last Friday I had Motul 10w-30 put in the engine, Amsoil Synthetic in the transmission, and LE-607 in the differential. I'm very pleased with the difference in pickup. The car now feels like it has an invisible "sail" on top pushing it. Previously, I was running Mobil 1, Honda MTF, and LE-607.

 

The viscosity recommended by Honda is either 10W30 or 5W30. If you choose to second guess Honda engineers, that is up to you.

0W40 oil will flow better when cold and maintains a thicker film when warm. I would be concerned about long-term viscosity stability and too high a viscosity when warm.

 

so which of the two listed would be more suitable for track purposes when the engine temp gets up. Note that I change oil every 4000 KMS, or after 1 track weekend.

 

I use 10W30 when tracking both my S2000 and Miata. Note that higher viscosity oils are often used in this "severe" service, but a racing "trick" is to use lower viscosity oils to increase power output.