Transaxle gear lube for Subaru

[Titan]

Well, since Specialty Formulation is not currently selling, and I've reached the 30,000 mile recommended mileage for their HDS-75-90 GL-5 gear lube in my Subaru, what do I try next?
AmSoil has a two 75-90's that would appear to work, a Severe Gear and a Long Life. Looks to me, like the Severe Gear is a bit of overkill in a Normally aspirated Subaru, but, I really want this car to last a quarter million miles or more.
Suggestions?

 

[unDummy]

I don't think that any extra protection is overkill. Use the severe gear for the front/rear ends.

 

[Thingfish]

In our Subaru club,( 1200+ members )I have been doing ALOT of Amsoil Severe Gear SVT 75/110 changes in manual transmissions and diffs, including mine. Non turbo through 550whp.
Everybody has had nothing but great things to say about it.
My rear diff in my WRX went from 159f to 102f with the same ambient temp and driving the same loop.

 

[Titan]

Two good recommendations. I'm sold on the idea. Just gotta look up Pablo's ordering information....

 

[Steve S]

Usually the transaxle will last untill something breaks, not from a lube problem if any top quality gear lube is used. When increasing the load then a move up in lubricants can't hurt. 75w/110 Amsoils marketing is incredable.

 

[Seth]

Catalog says svg lasts 50k under severe and 100k under normal. long life is supposed to last 500k which is preposterous if you ask me... Either that or I read the catalog wrong.

BTW, we are talking differential fluid. What about transfer case fluid? Is there an advantage in going with same fluids for both or different 75W90?

 

[Titan]

I use the same fluid in the front "transaxle" as the rear "differential". Both recommended to use a 75-90 GL-5 fluid.

 

[Thatwouldbegreat]

All three work well on our Outbacks

Amsoil SVG

Redline 75W-90NS

Specialty Formulations MTL-R

 

[gtx510]

RL 75W90NS is GL-5+ (GL-4/5) so that should work fine with synchros and hyploid gears. The center diff is viscous (same with the rear) and any front LSD (if there is one, STI only) should be helical (if you added a clutch type LSD you made a poor choice).

How does Amsoil SVG's additive content compare to RL 75W90NS? We need more gear oil VOA's...
SVG sounds like a regular GL-5, they say it can work in axles requiring GL-4 but don't mention synchro transmissions. MT-1 is for synchroless truck transmissions.
Amsoil Marine Gear sounds more like RL 75W90NS, it's GL4/5, but no mention of MT-1.
https://www.amsoil.com/storefront/agm.aspx

When will MTL-R be available again?

 

[TimVipond]

Amsoil will be releasing their "White Paper" comparison of gear lubes soon. Should be interesting.