Tranny and rear diff flush?

[Zac]

I'm looking for a good synthetic fluid to put in my tranny and rear diff. 98 ej22 with 5spd manual trans.

[Airgne]

AMSoil 75w90. fluch with lucus gear oil. i love it.

[rougeben83]

just use any good oil in the rear, you don't need anything fancy. People have used valvoline synth in the tranny with good results. I'm on Redline in the trans right now, shifts good, just like the Subaru Extra S - both popular/tried and true options.

DO NOT try the "scotty cocktail".

[anothernord]

just use any good oil in the rear, you don't need anything fancy. People have used valvoline synth in the tranny with good results. I'm on Redline in the trans right now, shifts good, just like the Subaru Extra S - both popular/tried and true options.

DO NOT try the "scotty cocktail".

Why exactly is Uncle Scotty's bad for the transmission?

[2.5GT]

I wouldn't even recommend any aftermarket "performance" fluids. OEM is good enough and doesn't cause leaks. And how hard do you have to drive in order to get that .5hp?

[Zac]

well I see -40'C in the winter alot and its hard to get into reverse when the fluid is thick thats why I want to try a synthetic. Oh well I'm going to the dealer to buy a wheel bearing and i'll see what they recomend.

[KAG]

Extra-S isn't synthetic but it is in fact the OEM fluid for Subaru's. So far it's worked wonders in 3 transmissions I've put it in.

It's most likely going to be hard to shift any transmission at -40C, you'll just have to get used to that.

[Airgne]

straight from amsoil website.

Product Description
AMSOIL SEVERE GEAR® Synthetic Extreme Pressure (EP) Lubricants are premium grade gear oils specifically engineered for maximum performance in severe duty applications. These state-of-the-art AMSOIL formulations feature an exclusive blend of high viscosity, shear stable synthetic base oils and an extra treatment of high-performance additives. AMSOIL SEVERE GEAR® Synthetic EP Lubricants maintain their viscosity for long-lasting protection against metal-to-metal contact. The proprietary AMSOIL additives form an iron-sulfide barrier coating on gear surfaces, providing the ultimate line of defense against wear, pitting and scoring. AMSOIL SEVERE GEAR® lubricants help prevent “thermal runaway” — a phenomenon caused by a lubricant’s inability to control friction and increased heat under high-stress conditions. By controlling thermal runaway, AMSOIL SEVERE GEAR® Synthetic EP Lubricants inhibit rapid lubricant degradation and component damage. Equipment runs better and lasts longer with AMSOIL SEVERE GEAR® Synthetic EP Lubricants.

Performance
AMSOIL SEVERE GEAR® provides performance beyond that possible with conventional gear oil. These AMSOIL custom products offer superior gear and bearing protection, better friction and heat reduction, increased efficiency and extended service life.

Superior Film Strength
Controls Thermal Runaway
Rust and Corrosion protection
Reduced Operating Temperatures
Improved Efficiency
Longer Oil, Seal, & Equipment Life
Temperature Extremes
AMSOIL SEVERE GEAR® EP lubricants excel in hot and cold temperature extremes. By design, they resist breakdown from high heat, preventing acids and carbon/varnish formation. Their waxfree construction also improves cold flow properties, improving fuel economy and cold weather shifting.

Applications
AMSOIL SEVERE GEAR® Synthetic EP Lubricants are excellent for severe applications, such as towing, hauling, steep hill driving, commercial use, plowing, racing, off-road use, rapid acceleration, frequent stop-and-go operation and high ambient temperatures.

Higher horsepower, towing and hauling capabilities of modern vehicles make turbo diesel pick-ups, SUVs, vans and delivery/utility vehicles especially prone to severe service. Other severe duty vehicles include light, medium and heavy-duty trucks, buses, heavy equipment, 4X4s, tow trucks, race cars, tractors, and motor homes.

For product service life in differentials, consult your owner’s manual or the Original Equipment Manufacturer (OEM) to establish the application, NORMAL or SEVERE.

. NORMAL SEVERE
Cars, SUV, Light & Medium Duty Trucks Drain at 100,000 miles of service or according to the owner’s manual, whichever is longer Drain at 50,000 miles of service or according to the owner’s manual, whichever is longer
Heavy Duty Class 8 Line Haul Follow the OEM drain interval (miles or hours) for synthetic oil up to 250,000 miles or 3 years, whichever comes first. Otherwise, drain at twice the OEM interval for conventional oil.
Heavy Duty Off-Road Vocational Follow the OEM drain interval (miles or hours) for synthetic oil up to 120,000 miles or 1 year, whichever comes first. Otherwise, drain at twice the OEM interval for conventional oil.

For product service life in non-differential applications, consult owner’s manual or the OEM for either normal or severe synthetic oil service intervals. Where service intervals are unavailable, drain at twice the interval for conventional oil.

Gear oils should be changed more frequently when operating vehicles or equipment in dusty or dirty conditions unless the gear system is properly sealed and equipped with membrane type breathers.

Note: AMSOIL does not support extended drain intervals where water contamination occurs. Check and service the gear oil frequently when water contamination is possible.

Recommended for use in differentials, manual transmissions and other gear applications requiring any of the following specifications: API GL-5, MT-1, MIL-PRF-2105E, Dana SHAES 234 (Formerly Eaton PS-037), Mack GO-J, or the differential (hypoid) gear oil specifications from all domestic and foreign manufacturers such as GM, Ford and Daimler Chrysler. Can also be used in axles where an API GL-4 lubricant is recommended.

AMSOIL SEVERE GEAR® (75W-90) provides superior performance and replaces competitors’ 75W-90 and 80W-90 gear oils. It delivers the best fuel efficiency and cold temperature performance of the SEVERE GEAR oils.

AMSOIL SEVERE GEAR® is compatible with conventional and synthetic gear oils. Mixing AMSOIL gear oils with other oils, however, will shorten the oil life expectancy and reduce the performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed. Aftermarket oil additives, other than those specified by AMSOIL, are not recommended for use with AMSOIL gear oils.

AMSOIL SEVERE GEAR® is compatible with most limited slip differentials. If limited slip differential chatter occurs, add AMSOIL Slip-Lock™ friction modifier additive.

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Material Safety Data Sheet (MSDS). An MSDS is available upon request at 715-392-7101 or on the AMSOIL website. Keep Out of Reach of Children. Don’t pollute. Return used oil to collection centers.

TYPICAL TECHNICAL PROPERTIES
AMSOIL SEVERE GEAR® Synthetic Extreme Pressure (EP) Lubricant 75W-90 (SVG)
Kinematic Viscosity @ 100°C, cSt (ASTM D-445) 16.7
Kinematic Viscosity @ 40°C, cst (ASTM D-445) 109.1
Viscosity Index (ASTM D-2270) 165
Brookfield Viscosity, cP (150,000 Max) @-40°C 68,150
Flash Point, °C (°F) (ASTM D-92) 150°C Min. 220 (428)
Pour Point, °C (°F) (ASTM D-97) -50 (-58)
Copper Corrosion (ASTM D-130) 1b Max @ 121 °C (250°F) / 3hr 1b
Falex Procedure B (ASTM D-3233) (failure load, lbf.) 2500
Foam Stability (ASTM D-892) (20/50/20 maximum) 0/0/0

[rougeben83]

Amsoil is ok, but just like the motor oil, you can usually find comparable oils for usually way less than the stuff they charge.




Why exactly is Uncle Scotty's bad for the transmission?


Part of it is the syncromesh that you put in, not very good on the brass/nickel components in the subaru transmission. But a lot of it is also because you're mixing in 3-4 different oils, each one having their own additive package that are of unknown consequence when theyre mixed together. The mixing also increases the replacement interval of the fluids, because mixed fluids tend to breakdown faster, so most people change it every 10k-15k because the shift consistency just degrades around that time.

When I used the cocktail, I took it out after around 12k miles for the reason stated above- it looked liked chunky chocolate milk. Some fanboys on NASIOC swear by it, but a few well known transmission rebuilders like DS1 and andrewtech have begun to advise people not to use the mix, and even scotty himself has admitted that he just mixed it in trial and error and didn't really think about the long term consequence of running such a variety of fluids in the transmission.

[Airgne]

agreed ben. if you look amsoil is 100,000miles.

[warrior]

on Toronto-Subaru-Club, a lot of guys are running the Gadget Guy mix.

In the rear diff, it's Redline Shockproof Heavy Weight (http://www.redlineoil.com/products_gearlubricants.asp?productID=44&subCategoryID=16&categoryID=6) and in the tranny/front diff, 3 litres of the 75W90 NS (http://www.redlineoil.com/products_gearlubricants.asp?productID=47&subCategoryID=17&categoryID=7) with 1litre of Shockproof Lightweight (http://www.redlineoil.com/products_gearlubricants.asp?productID=43&subCategoryID=16&categoryID=6)

This is a good thread with a bunch of people using different and very happy. I think it all comes down to preference. I'm going to change to the Motul for rear diff soon.

http://www.toronto-subaru-club.com/foru ... 459&page=4 (http://www.toronto-subaru-club.com/forums/showthread.php?t=119459&page=4)

[Huffer]

I'm going back to OEM for tranny and Redline for rear diff.

[dplacencia]

I use Royal Purple on by my subies. Trans, and rear diff, plus oil.