Subaru WRX Forums banner

1 - 20 of 115 Posts

·
Registered
Joined
·
382 Posts
Discussion Starter #1
Hi Guys,

I'm planning on swapping out my transmission and differential oil to the 75W-90 Amsoil offering shown here:
http://www.amsoil.com/storefront/svg.aspx

Manual Transmission: 3.7qt
Rear differential: 1.1 qt

I'll likely buy 6 quarts total to have some spare on hand, 5 might be playing it to close.

I know there is a lot of debate on NASIOC over what to use and a lot of people recommend the cocktail mix, but I feel better using a consistent mixture. Besides its a lot easier to put in and buy.

My goals are:
+ Superior protection
+ Better cold performance
+ Smoother transmission feel

I'll let you know how it turns out. (If I'm adventurous I'll try and do a write up for those looking to do the same.
 

·
Registered
Joined
·
3,474 Posts
Where's the How-To? ;)
I usually use the Subaru racing 75w-90 here myself in the suby but have also had great results with but amsoil, redline, mobil, and motul.

This would be a great post as a DIY
 

·
Registered
Joined
·
382 Posts
Discussion Starter #3
Where's the How-To? ;)
I usually use the Subaru racing 75w-90 here myself in the suby but have also had great results with but amsoil, redline, mobil, and motul.

This would be a great post as a DIY
Well, I've actually delayed the project for a couple weeks as I've had some home work come up. Once I do it, I will post the how-to for sure.
 

·
Registered
Joined
·
38 Posts
I run Amsoil in my KX450f race bike and it keeps everything super clan and i have had no wear issues at all over 2 years of run time. In my bike, the oil is used for both the motor and tranny. I love the amsoil stuff. I ran it in the WRX for an oil change but went back to Suby oil since I got free oil changes for 24,000miles. I'll be going back to full Amsoil through the rest of the car. From that small amount of time in the motor, I could feel a difference in the smoothness of the motor. It felt more willing.

I second the motion for a DYI.

Rock on.
 

·
Registered
Joined
·
954 Posts
so the trans and the rear diff both use 75-90w?
 

·
Registered
Joined
·
3,474 Posts

·
Registered
Joined
·
382 Posts
Discussion Starter #7
Well, the extra projects at home have really tied up my time combined with projects at work, so still no go. I plan to do this for sure before Christmas, as I have a large trip planned. It will get done, just is taking longer then I hoped, sorry for the delay.
 

·
Registered
Joined
·
3,474 Posts
Better late than never :)
 

·
Registered
Joined
·
382 Posts
Discussion Starter #9
Well...

No way I'm going to have it done before Christmas, short of a miracle.
I know a lot of you are waiting on the edge of your seat, so hang in there. ;)
 

·
Registered
Joined
·
4,657 Posts
GM Syncromesh Friction Modified fluid is really good transmission fluid in my experience. I will absolutely be using that when it's time to change the fluid, or I want to smooth the shifting a bit more. Make sure it's the friction modified fluid though. The regular syncromesh fluid isn't that great and breaks down a lot faster. It's also sold under AC Delco and a couple other brand names, but it's the same stuff as long as it's the syncromesh friction modified. Honda guys use it to fix the 6 speed transmission issues they have, and it works wonderfully. Maybe swapping the penzoil syncromesh out of the cocktail in favor of the syncromesh friction modified would be a good idea?
 

·
Registered
Joined
·
2,678 Posts
I know I'm bringing up an ancient thread here... but I basically am about to do the same thing. Has anyone done this yet and been OK with just 5 quarts? I'm debating getting a 6th quart but I don't want to spend an extra $12 if I don't have to.

I'm ordering the Extra S fluid from Fred Beans... just wanna make sure 5 quarts will be enough before I hit the "complete order" button Lol

http://www.fredbeansparts.com/servlet/the-1206/Subaru-Extra-S-75w90/Detail
 

·
Registered
Joined
·
3,869 Posts
I know I'm bringing up an ancient thread here... but I basically am about to do the same thing. Has anyone done this yet and been OK with just 5 quarts? I'm debating getting a 6th quart but I don't want to spend an extra if I don't have to.

I'm ordering the Extra S fluid from Fred Beans... just wanna make sure 5 quarts will be enough before I hit the "complete order" button Lol

http://www.fredbeansparts.com/servlet/the-1206/Subaru-Extra-S-75w90/Detail
4 is enough, I have one left over. Did one oil change with Subaru fluids then switched to Redline (no friction modifiers for trans), feels much better.
 

·
Registered
Joined
·
2,678 Posts
I know I'm bringing up an ancient thread here... but I basically am about to do the same thing. Has anyone done this yet and been OK with just 5 quarts? I'm debating getting a 6th quart but I don't want to spend an extra if I don't have to.

I'm ordering the Extra S fluid from Fred Beans... just wanna make sure 5 quarts will be enough before I hit the "complete order" button Lol

http://www.fredbeansparts.com/servlet/the-1206/Subaru-Extra-S-75w90/Detail
4 is enough, I have one left over. Did one oil change with Subaru fluids then switched to Redline (no friction modifiers for trans), feels much better.

4 is enough? I thought the trans takes 3.7 and the diff takes 1.1???
 

·
Registered
Joined
·
3,869 Posts
I know I'm bringing up an ancient thread here... but I basically am about to do the same thing. Has anyone done this yet and been OK with just 5 quarts? I'm debating getting a 6th quart but I don't want to spend an extra if I don't have to.

I'm ordering the Extra S fluid from Fred Beans... just wanna make sure 5 quarts will be enough before I hit the "complete order" button Lol

http://www.fredbeansparts.com/servlet/the-1206/Subaru-Extra-S-75w90/Detail
4 is enough, I have one left over. Did one oil change with Subaru fluids then switched to Redline (no friction modifiers for trans), feels much better.

4 is enough? I thought the trans takes 3.7 and the diff takes 1.1???
Excuse me, I wasn't thinking. 4 is enough for trans...I use different fluids for trans and diff. 5 is definitely enough, I think a whole bottle was actually too much for the rear diff.
 

·
Registered
Joined
·
3,474 Posts
I've done my STi 5 was pretty much perfecto.
 

·
Registered
Joined
·
2,678 Posts
Awesome! Thanks for the insight guys!!! Ordered 5qts last night!!! Cant wait to get it changed out... the gears feel a little tight and the new fluid should make a nice difference ;D
 

·
Registered
Joined
·
92 Posts
I'm wondering, for the Rear Diff on the WRX (not STI), if it would be safe to use almost any GL-5 75w-90 oil rather than spend the extra cash on Extra-S? Has anyone had any negative experience with using over the counter GL-5 oil in the rear diff of the standard WRX?
 

·
Registered
Joined
·
3,474 Posts
I'm wondering, for the Rear Diff on the WRX (not STI), if it would be safe to use almost any GL-5 75w-90 oil rather than spend the extra cash on Extra-S? Has anyone had any negative experience with using over the counter GL-5 oil in the rear diff of the standard WRX?
I wouldn't say negative but some oils like to be warmed up more than others.
 
1 - 20 of 115 Posts
Top