jojipoji

Obviously this isn't a proven claim that I have actual facts to back up my observations but i recently put in amsoil in April. Every year I change my diff fluid in the spring. I typically drive my s2000 until november. Over the 10 years I've owned my different s2000s I have always used Mobil 1 diff or redline shock fluid for the diff. I always find a small amount of shavings on the diff bolt (drain). I track and autox my car and this year i tracked it a few more times than normal so I decided to change it a bit earlier. This spring I used amsoil for the first time because I bought a case for my ctsv. When I drained the fluid it was a little dirty but not nearly as dirty as the Mobil 1 gets. In addition there was very little traces of shavings (black sludge) on the drain bolt. Probably 1/8 than normal.

From what I visually see I really like the fact that the fluid was less dirty and there was a significant amount of less shavings on the drain bolt despite more mileage and track days this year. Just throwing it out there for your comments. Obviously tis isn't a purely comparable test with my previous diff fluid changes but i did notice a difference.

bsconz

Thanks for posting this. I've been reading everything I could find on the diff oil debate as I'm about to do mine for the first time (I just bought an 07 with about 26K on it). I was debating between Mobil-1 and Amsoil but I think this was all the information I needed to tip the scale towards Amsoil.


What weight did you use? 75W-90 or 75W-140?

Saki GT

Unfortunately visual inspection of oil is not a very reliable indicator. Given the nature of different oils, some may just brown over time with age and use and not because they are more or less dirty.

Still, its entirely possible that Amsoil is lubricating a bit better and minimizing wear, which leads to cleaner-looking oil. Some UOAs on Mobil1 and Amsoil back to back would be the best determinate. The drain bolt tells a better story than oil color.

Fwiw, I've run Amsoil and Mobil1 in my diff and the oil seems clean after every change regardless which is used. Also, the magnetic drain bolt never had much metal on it.

I get less whine/lash with 110 usually, unless the diff is really hot. Mobil1 is just easier to get than Amsoil, which is why I usually use it.

s2000maniac

go with 75w-110

Billman250

Time does nothing to dif fluid like it does engine oil, because there is no fuel dilution. Mileage is a primary key factor. How many miles? if its a few k miles, I would expect it to be clean.

I use Mobil1 75w90 in my car and ALL my customers.

Even at 40k miles on the fluid, the fluid come out like brand new. And I seriously mean brand new in appearance.

In addition, the magnet has virtually no trace of metal...not even a slight bit of grey paste. This is consistent car after car. This is my proof.

This has proven on hundreds of s2ks with all different setups, including mine (and you guys now how i drive mine) dragon, drifitng, autox, track, and it still comes out like brand new.

Say what you will about Amsoil. I'm sure it's great.

Everyone can take this to the bank...Mobil1 to me has been the ultimate fluid and I wouldn't even think of trying another with the amount of time I've spent with Mobil1.

Use Mobil1 75w90 with 100% confidence.

Arthas

Iv yet to change my diff fluid after using amsoil in the diff, iv delt with mobile1 but thought id try amsoil in my diff since I always use it in my motor oil. Not sure if I should be expecting anything less or greater than mobile. But if its as good as its motor oil, I don't plan on going back to anything else.

Billman250

So many opinions and views on oils and stuff....makes it hard...

All I know is my car has been on Mobil1 10w30, since 600 miles when it was new. I am now at 118k.

I couldnt be happier with my power output, compression, lack of oil burning. The car feels faster every year. I offer anyone to go for a ride with me in my car at a meet you wouldnt believe how fast it is until you sit in it.

Arthas

^ omw

zeroptzero

I`ve seen your Dragon videos, I don`t think I could stomach a ride in your car . I`ll just take your word that it is a great fluid.

Saki GT

LOL.