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2016 WRX Prem

I was looking into changing my front/rear diff oil since I've now hit 25k miles. I talked to the Subaru dealership and they said that the oil for the front and rear diff is the same....Subaru High Performance 75W-90.

Do others use the same gear oil for both?
 

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In the past I have used slightly different oils.. since the transmission is synchromesh I used oil with friction modifiers in the transmission (front diff) and in the rear I used the same oil, only without the friction modifiers. IIRC I was using Redline at the time. Technically oil without friction modifiers should result in less wear since it's "slicker".. in the real world I doubt anyone would be able to tell a difference.
 

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2011 sti here. I used Subaru's gear oil in both front and rear. They used to have two different oils, but they did away with that. The same gear oil in both is what is recommended.
 

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I'm not sure if this has changed (I should probably look into it), but the STI used to have different friction modifier requirements compared to the WRX.

Extra S has always been great.
 

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That has not been my experience.. but in light of virtually everyone else's reviews, I suspect that's not what actually ended up in my transmission when I had the dealership change it.
I understand that AMSOIL is also good, but Extra S produced the most positive shift feel in my bugeye compared to Redline, USC, or standard Subaru fluid.
 

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Extra S has always been great.
FWIW, Subaru no longer makes Extra S (EDIT:makes probably wasn't the right term; uses or supplies. Essentially, Extra S is no longer available or used by Subaru). They now have one universal high performance 75w90 gear oil used for both transmission and differentials. Had a discussion with the dealership about this just 2 months ago before purchasing 6 quarts for my transmission and rear diff.
 

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FWIW, Subaru no longer makes Extra S (EDIT:makes probably wasn't the right term; uses or supplies. Essentially, Extra S is no longer available or used by Subaru). They now have one universal high performance 75w90 gear oil used for both transmission and differentials. Had a discussion with the dealership about this just 2 months ago before purchasing 6 quarts for my transmission and rear diff.
Good thing I still have a jug of Extra S in my garage...
 

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I understand that AMSOIL is also good, but Extra S produced the most positive shift feel in my bugeye compared to Redline, USC, or standard Subaru fluid.

Amsoil seemed really good in my transmission.. I'd say Redline was the second best that I've tried, then the conventional gear oil that came in it from the factory. The gear oil that was supposedly Subaru synthetic seemed like it was too slick for the synchros. It would shift fine if I gave it a short pause between gears, but if I shifted rapidly like I normally do 3rd to 4th would grind every time. After about five months I was sick of it and swapped it out for Amsoil.
 

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Amsoil seemed really good in my transmission.. I'd say Redline was the second best that I've tried, then the conventional gear oil that came in it from the factory. The gear oil that was supposedly Subaru synthetic seemed like it was too slick for the synchros. It would shift fine if I gave it a short pause between gears, but if I shifted rapidly like I normally do 3rd to 4th would grind every time. After about five months I was sick of it and swapped it out for Amsoil.
I had TERRIBLE experiences with Redline. Interesting our discrepancies.
 
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