Looking for a LSD trans fluid for a subaru

[Ammadien]

So I've decided to go with the stock LSD fluid for the rear-end on my 2005 STI. But I'm trying to find an adequate(or better than adequate) gear oil for the 6-speed.

Daily driver, 100 miles round trip daily, 45-55 mph, with occasional more fun jaunts/1/4mile drags,

Narrowed it down to a few:

Owners manual says API class. GL-5 75w/90

15k intervals for"severe driving conditions" makes me feel good about buying a more pricey gear oil.

AMSOIL's 75w/90


Or Redline's

Redline 75w/90

Stock:

Subaru Gear-S

Now I plan to re-work the motor at some point(130k+) but would like the transmission and rear-end to hold up well beyond that.

Thoughts and opinions welcome. Amsoil seems completely dependable.

Nate

 

[unDummy]

http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil1_Synthetic_Gear_Lubricant_LS_75W-90.aspx

 

[Herz]

Originally Posted By: unDummy
http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil1_Synthetic_Gear_Lubricant_LS_75W-90.aspx


Mobil1 gear oil is the worst stuff I have ever used in a transmission.

Out of the two, i'd use Amsoil

The Mobil1 made my Jeep shift like a bloddy nightmare, did it to my friends 05 corrola too.

 

[gathermewool]

Can't go wrong with the Extra S. When I do mine, it'll either be Extra S or Motul Gear 300.

 

[gathermewool]

I've got data for several gear oils I was considering for my rear diff change out in an excel spread sheet. Motul was the most expensive, but was the best on paper, especially compared to non-exotic OTS oils like Valvoline and Mobil 1.

Here's what I found for Motul Gear 300:

Motul 300
Price/qt 20.00
Density 15C 0.9
Viscosity 40C (cst) 72.6
Viscosity 100C (cst) 15.2
Viscosity Index 222
Flashpoint C 200
Pour Point C -60

 

[Ammadien]

Ahh I'd forgotten about Motul, something to consider as well. Thanks for your input everyone.

Nate

 

[unDummy]

I misread the request.

For the rear-end, any 75w90 synthetic will work fine.

For the manual trans, you want a non-LSD gear oil.

Ford, Torco, Synlube, Redline, Amsoil, RoyalPurple, BG, Neo, Silkolene, Eneos, Idemitsu.... have GL5 gear oils that either don't have LSD additive, or are manual transmission friendly.

 

[gathermewool]

His rear end has a clutch-type LSD, so a LS lube is required. '07+ STI's have the Torsen.

 

[Ammadien]

Right, gonna use the stock LSD differential gear oil.

hmm..

 

[unDummy]

LSD additive is needed whether it comes with the lube or not. Nothing special!

 

[Ammadien]

For the rear end I meant lol...sorry if that was confusing

Nate

 

[gathermewool]

Originally Posted By: unDummy
LSD additive is needed whether it comes with the lube or not. Nothing special!



What do you mean? Could you explain please?

Maybe what I said was confusing. I meant to say that the pre-'07 STI's have a clutch-type LSD in the rear, and need the friction modifier. The '07+ are gear-type Torsens, which don't require anything more than a good GL-5 lube. I'm sorry for taking this so far OT, but wanted to clear that up.

For front, LS additive or no, it doesn't matter. It seems like you've got things under control

 

[Tremo]

For Subarus (I own 2 of them), any good GL5 will work in the rear. If you have LSD, then use an oil with LS friction modifiers.

For the manual transmission, you still have to use GL5 because it shares lube oil with the front differential. But, do NOT use oil with LS friction modifiers. Extra-S, Motul, Neo, Redline NS, etc.

Guys on the Forester forum use a cocktail which also includes Redline lightweight shockproof mixed with Motul. I was skeptical till I tried it, I'm a believer now. Shifting in my Outback's 5MT is way better with the shockproof added.

 

[Ammadien]

Ya i'm leaning toward the shockproof, people seem to like it and I found cases at about 8 dollars per quart less than the motul. This is for the transmission.

I think the guy before me put mobil in it and It's been more notchy the longer it goes so we'll see.


Thanks for the input.


Nate

 

[waltb]

I am using M1 in my Outback 5sp. It is ok but not great. The transmission has always been a bit notchy even with the original fill. I think I will try the Red Line 75W-90 NS next time.

 

[gathermewool]

Originally Posted By: Tremo
For Subarus (I own 2 of them), any good GL5 will work in the rear. If you have LSD, then use an oil with LS friction modifiers.

For the manual transmission, you still have to use GL5 because it shares lube oil with the front differential. But, do NOT use oil with LS friction modifiers. Extra-S, Motul, Neo, Redline NS, etc.

Guys on the Forester forum use a cocktail which also includes Redline lightweight shockproof mixed with Motul. I was skeptical till I tried it, I'm a believer now. Shifting in my Outback's 5MT is way better with the shockproof added.


Only the clutch-type require the friction modifier. Gear-type LSD do NOT require any LS additive.

Do you mean Uncle Scotty's Cocktail? I've heard mixed reviews myself. I really can't believe that adding multiple gear oils together is a good idea, but that's just my opinion. Motul seems to be the best on paper, with Redline NS being my second choice for the gearbox. Here's a link the to the Redline NS http://www.redlineoil.com/product.aspx?pid=47&pcid=7

 

[sprintman]

Redline 75W90 in our Subaru Outback diff.

 

[aquariuscsm]

I`d go with either the Amsoil or Redline. I keep hearing good things about NEO and Motul also.

 

[dparm]

Motul Gear 300, Eneos MT, Maxima Syn Gear, or Lubro-Moly Vollsynthetisches Getriebeöl. Top performers and all are readily available in the US.

 

[SubLGT]

Originally Posted By: gathermewool
Can't go wrong with the Extra S. When I do mine, it'll either be Extra S or Motul Gear 300.


Which one did you finally end up with in the transmission?