After doing some searching here on the forums and noticing that the threads are all over the place as far as fluid choices go, I figured I would start a pole with a poll to see the numbers of users of each fluid and the reasons why they use it.

**Please include your choice of fluid in your reply, why you chose it, if it created or eliminated any grands or notchiness, and lastly if you do any racing with your car.

The Choices I have included: (in no specific order)


Six Speed Transmission:


AMSOIL: Synthetic Manual Transmission and Transaxle Gear Lube 75W-90 API GL-4 (MTG)

Mitsubishi: DiaQueen - 75W85 GL-4 (mineral type oil)

Motul: Motylgear 75W-90 - GL4/GL5 (synthetic blend) /or/ Motul: Gear 300 75W-90 - GL4/GL5 (fully synthetic)

Redline: MT-90 75W-90 GL-4 Gear Oil

Royal Purple: Max Gear 75W-90 GL4/GL5



Transfercase and Rear Differential


AMSOIL: SEVERE GEAR® Synthetic Extreme Pressure (EP) Lubricant 75W-140 (SVO)

Mitsubishi: DiaQueen LSD Gear Oil SAE 90 (mineral type oil)

Motul: Gear Competition FF Gearbox & LSD Oil - 75W-140 (fully synthetic)

Redline: 75W-140 GL-5 Gear Oil

Royal Purple: Max Gear 75W-140



Also I am sure I may have left some brands off the list, If you are using a different brand that is working well, please post it up and I will add it to the list.


Thank you.

 

I had Royal Purple fluid put in when I had my clutch changed, just gauging other Evo owners on other options.

 

Royal purple since I changed the clutch 30k ago. My old boss had a fully built 67 cudda with a 300 shot of nos, and he went with royal purple. I figured if it is good enough for a 9 second car its good enough for my baby. Just changed the fluid last weekend for the first time since the clutch(I know I know!) and the fluid looked brand new. Imo any that you have listed would be a great choice, good luck!

 

Oem ftmfw.

 

Do you have the Part number for thr Royal purple fluid?

 

I used max gear 75w-90

 

I used Amsoil for the transmission fluid and OEM Diaqueen for the TC/Rear Dif.

I have a 5 speed if that matters.

 

OEM in my 6sp!

 

castrol syntorq LT for tranny

 

I've used OEM, castrol syntorque, and redline MT-90.. all three feel about the same to me. No hard data here showing ones better than the other...

 

I use AMSOil in everything and love it, have never had any problems, I've noticed that it keeps running temps down, which is great for everything involved since the 6sp is known for having heat issues. I don't plan on ever using anything else.

 

***UPDATE!

It seems that Motul Gear 300 (trans) is fully Synthetic. I am trying to do some research now on weather this is a good or a bad thing for Mitsubishi transmissions. Motul also sells "Motylgear" 75W-90 that is a synthetic blend. I am going to try and get in touch with a rep from Motul to get the specifics, also talk to Mitsubishi about what they recommend.


Both listed below:



GEAR 300 75W90 100% ESTER SYNTHETIC

Motul's highest quality 100% ESTER BASED synthetic 75W90 gearbox oil. Designed for today's high performance vehicles, and all out race cars. This lubricant is virtually unshearable. Its stability at high temperatures make it ideal for extreme conditions. Many endurance professional race teams swear by this oil. Designed for transmission gearboxes and rear axles. API GL4 and GL5/MIL-L-2105C.





MOTYLGEAR 75W90 SYNTHETIC BLEND GEARBOX OIL

A great high performance synthetic blend gear oil for gearboxes and rear ends. Perfect for older boxes that are harder to shift and have a tendency to "snick" or "grind" going into gear, this oil has additives which help to reduce gear mesh. A strong friction reduction package increases mileage, while extending the life of the gearbox.
API GL4 and GL5 MIL-L2105C.

 

Id be careful using too exotic of an oil in the transmission. The evo trans is very picky. If you put in the wrong oil it makes for very notchy shifting especially when it's cold. From what I hear the way the syncros work it needs a certain amount of drag in the fluid. It must be a GL4 not any kind of all purpose GL4&5 stuff.

I definitely wouldn't use a synthetic blend if I had the choice. Full synthetic for sure. I ran royal purple max gear in my tcase for a year and had no problems with it. When I changed my clutch it was all I could find locally that fit the specs.

 

Does anyone know if stock DiaQueen is fully synthetic or synthetic blend?

 

non of the above, Diaqueen is a mineral oil type.