Just wanted to mention that Amsoil just released a new study on GL-5 gear lubes that compares the performance of a large number of different brands of gear lubes. The study appears to independently run/audited and be very comprehensive. Amsoil includes their 75W-90 EP gear lube in the study, and while it doesn't win any of the tests, it consistently performed very well.

Both the 5-speed and 6-speed call out GL-4 oil, so the study is not directly relevant to the Evo, but its nonetheless a nice study worth reading. Now if Amsoil would just do the same with GL-4 oils.

Here is the page:
http://www.amsoil.com/products/gearl...hitePaper.aspx

Here is a direct PDF download link:
http://www.amsoil.com/lit/g2457.pdf

 

Interesting, thanks for posting

 

The transfer case and rear diff both use GL-5, which is what these gear oils would be used for.

 

Correct! I just bought Amsoil to run in my transfer case and rear diff. If anyone wants to buy Amsoil contact Oil Doc on this site, awesome prices and great service!

Mike

 

The Diaqueen is listed as LSD oil. Is there any requirement for proper LSD action?

 

I dont know but I've been running the diaqueen in the front and rear on my VIII 5speed GSR for 50,000 miles and everything still works (I hope)

 

one thing i can add is, royal purple is garbage in the cold.. i have had it my tranny for 2 months.. soon as it got cold it was a pain to switch gears for the first half an hour of driving.. overall even warm the tranny is notcier than any other oil i have tried..

i know i should have went wiith amsoil. hell i ran it in my banshee for 3 years, and the rings still looked perfect.


so if you live in the cold dont run royal purple. i have an 05 with less than 10000 miles on it.

 

i always knew amsoil was good, they remained very consistent throughout all the tests.

 

I spoke to Amsoil yesterday afternoon. Their EP gear lube in the test also passes a MIL spec standard that requires compatibility with copper alloys (brass), so it can be used in the gearbox with no material compatibility issues, and its much more wear resistant than a GL-4 lube. There are no additives to assist in syncro action though, so the guy said shifting may be stiffer. I'll probably give it a try.

 

I would have like to see some of the Motul fluids in the test. I think they would have given Amsoil a run for their money or maybe even beat them. Maybe I will have to try Amsoil soon...it already works good in my engine.

 

Amsoil makes a GL-4 trans fluid that works very well in the Evo tranny. I've been using it for over 20,000 miles without issues.

-Paul

 

which one is their gl-4?

 

MTG

 

very interesting to see that the stock Mobil 1 fluid came in 4th from last! this might help explain y it was easy for 03-04 evo spider gears to get chewed up once ppl turned up the wick.

when i changed my xfer case fluid at 5k miles, it had only 1/2 the amount of measured fluid it supposed to have had. either they didn't put much in for break-in, or it mysteriously burnt up due to heat.

once i changed all the fluids to royal purple, it ran waay smoother. Motul works even better & has the only fully synthetic gear oil, but since i'm not building a dedicated racecar, i don't think the extra cost is warranted.

 

I don't put a lot of credit in manufacturer-backed "studies," and Amsoil more than any other company is a culprit. Pushy salesmen who try to beat you over the head with these so-called "studies" to get you to buy it...