I want to change the transmission and rear diff fluids in my RX soon and have searched here for threads on the fluids to use. I have been able to find suppliers online for both Subaru OEM fluid (the Extra-S stuff) and the Redline 75W-90NS which seems to be the most popular and recommended aftermarket brand. Is one of these better than the other or can I go with either? The Redline fluid is cheaper by a few dollars, so if they are virtually the same, that is what I will likely go with.

 

I have also found the Subaru LSD oil (part # K0305Y0900) online as well. Would the alternative be adding the Redline LSD Friction Modifier to the 75W-90 I will put in the transmission?

I run the Subaru Factory Extra-S gear oil in the trans and Subaru LSD oil in the Rear diff on my RX.

 

Its much better than whatever was in there from the previous owners

I thought Extra-S was only available in big containers.

 

Jacob

I thought Extra-S was only available in big containers.

 

Jacob

 

Not if you know where to look.

 

http://www.fredbeansparts.com/index.php/subaru-75w90-extra-s-gear-and-transmission-quart-bottle.html

Not if you know where to look.

 

http://www.fredbeansparts.com/index.php/subaru-75w90-extra-s-gear-and-transmission-quart-bottle.html

 

Wow. I've never heard of that before. A lot of people have been buying the big containers and trying to sell what they don't use.

 

Jacob

i've only gone from dino to synthetics and never noticed a difference, is it really worth going to this stuff in an average daily driver?

i've never tried relieving any particular issue, so if everything is working smooth is there an advantage to using this stuff?

i've only gone from dino to synthetics and never noticed a difference, is it really worth going to this stuff in an average daily driver?

i've never tried relieving any particular issue, so if everything is working smooth is there an advantage to using this stuff?

 

There is an advantage, but whether it's worth it for you is up to you, of course. If you don't have a problem with what you have now, then you probably shouldn't mess with it.

 

I've tried a few different oils in my 6-speed. This stuff has been the best so far. You can shift into first going probably 15 mph. Maybe even more. Also, you can shift into 2-6 in the bitter cold before things get warmed up. All of the other oils I've tried have put up a fight until things get warmed up.

 

Jacob

There is an advantage, but whether it's worth it for you is up to you, of course. If you don't have a problem with what you have now, then you probably shouldn't mess with it.

 

I've tried a few different oils in my 6-speed. This stuff has been the best so far. You can shift into first going probably 15 mph. Maybe even more. Also, you can shift into 2-6 in the bitter cold before things get warmed up. All of the other oils I've tried have put up a fight until things get warmed up.

 

Jacob

 

Is that the Extra-S you are referring to?

Is that the Extra-S you are referring to?

 

Yeah. Upon reading my last post, I realized that I didn't specify.

 

Jacob

We have it where i work also in quart sized bottles

 

http://forums.nasioc.com/forums/showthread.php?t=1946774

Go with the Redline. It is amazing stuff...I have a very notchy 4 speed gearbox behind my EA81 and the Redline is by far the best gearbox fluid I've ever used. I've tried all sorts of fluids and additives in the time that I've had the car.

I second the Redline MTL, never used the Subaru fluid. My old Brat's 4-speed was pretty notchy and MTL made a very noticable improvement. Especially on very cold mornings!

I have used Redline synth, Amsoil synth, "Scotty's Cocktail", Valvoline w/Rislone, Castrol HypoyC w/rislone, Straight HypoyC.

 

 

Extra-S blows them all out of the water. I'll never use anything else in any Subaru MT.

I Believe that No one here have Tried Gearbox fluid Reinforced with Molybdenum bisulphide MOS2... it does Wonders on Old Gearboxes and Differentials; let me Explain.

Since that Kind of Gearbox Fluid is Designed to Extreme Pressures and to leave a Protective Film, its Molybdenum bisulphide MOS2 Makes any Hard-to-Shift Gearbox to go Smooth as Silk, also it Removes a Great Percentage of the Gearbox Noise.

I Drive my Subies and my Old Mercury comet with this:

 

 

Motul 80W~90.

(I Also use Motul Motor Oil for my cars' Engines)

 

For More information, see:

http://shop.edoperformance.com/motul-gearbox-80w90-api-gl4-gl5-105-p-15036.html

 

Due to the Molybdenum, the Fluid Looks like Black Oil, Black as Graphite Grease for C.V. Joints.

Believe me: Once you've Tried this Black Oil, You'll Never Want to come back to Standard Fluids.

Kind Regards.