I'm really sorry to beat a dead horse but I wanted to triple check that I'm looking at the correct diff fluid.

First, it should be noted that I live in Wisconsin and the car is driven once in awhile during the winter when it is dry, so it would see temperatures around 25-30 degrees. The S is stored in an insulated garage, so it is warmer in there than outside (if this helps). In the spring/summer it will be autocrossed, and maybe looking at doing a track day.

I have read the oil journals and I noticed 3 options that people seem to like:

1) LE 1605
2) Mobil 1 75W-90
3) Amsoil 75W-110

Are any of these options more prone to pre-mature wear or failure?

Thanks again.

 

skip Mobil 1, LE 1605 is great, you can get it for 15$ a quart, its thick has to be heated to pump it.

amsoil should be fine.

 

I'm going to throw out another option. Bel Ray Gear Saver 80W-90. I have been using it for 10 years in my heavily autocrossed S. I change it yearly and have never had an issue. It is a GL-5 Hypoid gear oil as recommended in the Owner's manual. Best part is it is available at most motorcycle shops.

 

But wait there’s more! 75/140 is what I started using last year and is what Puddydad "the diff guru" recommended. I am sold on it now that ive put a good 20k with it. I think its a must for diffs that have some mileage on them/loser tolerances. Mine is quiet and felt smoother/rejuvenated when I swapped this in.

 

Holy Options!

Really? I didn't know LE-1605 had to be heated. Would I have to wait until spring to change the fluid, or just heat the bottle somehow? (I don't think the diff fluid has ever been changed)

I'll have to see if my local motorcycle place has it. I should be driving by there tomorrow anyways!

My S only has 15K miles on it, but I will keep this in mind.

Thanks for all your help guys!

 

I saw dramatically reduced wear numbers using LE1605 in used fluid analysis samples that I took on my rear diff. I ran Amsoil 75w110 and Amsoil 75w140 , and LE1605. Iron wear numbers dropped to 25% of what they were with the other fluids and despite me running the LE1605 twice the distance. My used fluid sample is on this forum somewhere.

The only caveat is the low temperature numbers, I don't drive my car in winter though. But it is good for the temps you listed in your original post, plus the fact that you have a heated garage surely helps. As far as heating goes, just stick the bottle in a tub of hot water and let it warm up before using. Keep it at room temperature before using, then heat it up in some hot water 10 minutes before you go to use it. It just makes it easier to pump that's all. But I now use a funnel and hose method for fill my diff (which I find easier than pumping).

 

Just the other day, Shad at Driving Ambitions neat Sacramento recommended that. Going to try it out.

 

FYI...The Amsoil 75-110 is $12qt and the 75-140 is $13....for Preferred Customers.

I run the 75-110 in my 03S & 02Z.

\rlr
Carolina

 

Mobile 1 75w-90 for 10+ years. No issues and no wear (as evidenced by my Blackstone Reports). I tend to trust what Honda recommends.

Works for me........

Utah

 

LE 1605