Thats not really a valid point here. At all.

 

In relation to the thread title? No. In relation to the efficiency comment? Sure

 

Saki GT Posted on Jan 17 2011, 09:03 PM
Even for normal use the average 2011 SAE 75W-90 is a lot thinner than the old school (recommended by Honda) SAE 90, the SAE 110 is pretty much the same.

(IMO) Sure, you will get some more oil drag with thicker oil but that might be cancelled out by the loss of friction at pinion/ring contact.

And I believe, based on personal experience, the Torsen will work better with oil with better EP qualities.
Less locking in tight corners.
A change in Torsen behavior after nothing but a diff oil change.

 

Thanks for the explanation S. I know the old 75w90 class split and 75w110 seems a good choice for S2000s today, but people use 75w140 in trucks that tow, so I wonder if it is excessive for such an application in the S2000 that doesn't see track time or desert use.

Does anyone know the normal operating temps for the diff at say highway speeds?

 

At these point I've measured about 63C after some spirited driving - with SAE 90.
22C ambient.
Last year I've measured the oil itself while draining and found 69C, ambient 18C.
That was with SAE 190.

Who knows what the oil temp is at pinion/ring contact.
It could be high, even for a very short time.

Btw.. Richmond Gear recommends 75W-140 for all their gear sets.

 

 

SpitfireS is the go to guy when it comes to lubricants. Marc has been a great help to me and many others over the years

75/110 or 75/140 are both fine to use. 75/110 for the daily driver and 75/140 for built rears and track use. Amsoil is my top choice

 

Success! saved myself 350 and did the differential install my self!! everything went well! i think ill do it faster the next time around.

 

S2KPUDDYDAD and SpitfireS,

Thank you both for your wealth of information. I did have an additional question...

How often would you recommend changing the differential fluid for regular street use? How about for low mileage cars (garage queens); would you recommend based on time rather than mileage?

Thanks,
Chris

 

+1 for puddydaddy, i think ill be havin a diff for him soon, i sell amsoil, simply because its the best crap ive seen in a differential. Severe Gear 75w110 is amazing. My advice on fluids has to be Valvoline syn power for engine, GM Synchromesh Friction Modified for tranny, and Amsoil Severe Gear 75w110 for diff. you wouldnt be happier with anything else.