Have an 07' NA Subaru and am thinking about the gear oil wearing the synchronizers. GL5 is recommended, but 5 is for a rear, and GL-4 is for a trans. Being a transaxle up front it seems like something between the 4&5 would be better. 5 is said to have more EP extreme pressure adds for a rear, that isn't good for synchronizers if a yellow metal. Being AWD, it seems like the axle in the transaxle wouldn't have the pressures on the gears that a FWD or RWD axle would, since half the power goes to the rear axle. Supposed to be that the angle of the pinion gear on the ring gear determines the pressures. Even thought of adding some straight mineral oil from a drug store to the oil, but don't want to make things worse.
Transaxle oil?
- Thread starter VinceF
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Don't think too much about it. Use whatever the Subaru recommends.
I would not put in a GL-5 oil in a GL-4 recommended axle/transmission. GL-5 is not backward compatible with GL-4. It has different friction modifiers and can wreck a transmission especially a Nissan gearbox.
I would not put in a GL-5 oil in a GL-4 recommended axle/transmission. GL-5 is not backward compatible with GL-4. It has different friction modifiers and can wreck a transmission especially a Nissan gearbox.
Stick with the oem recommendation. I would not add anything that isn't approved by the manual.
The recommendation is a GL-5 - with 75W90 being the preferred weight.
The biggest issue isn't going to be the EP additives but the LSD additives required for GL-5.
You might try Red Line 75W90NS. It's formulated like a GL-5 75W90, but without the LSD additives.
The biggest issue isn't going to be the EP additives but the LSD additives required for GL-5.
You might try Red Line 75W90NS. It's formulated like a GL-5 75W90, but without the LSD additives.
Originally Posted By: y_p_w
The recommendation is a GL-5 - with 75W90 being the preferred weight.
If the blocking rings in the transmission are brass then this is a big no-no.
The recommendation is a GL-5 - with 75W90 being the preferred weight.
If the blocking rings in the transmission are brass then this is a big no-no.
GL-5 is correct for the application. Get a 75w-90 without LSD additive. The Red Line NS that was previously mentioned is a good choice. I plan to use plain Valvoline 75w-90 in mine when the time comes.
Originally Posted By: Bandito440
GL-5 is correct for the application.
Then the OP (VinceF) must be mistaken.
GL-5 is correct for the application.
Then the OP (VinceF) must be mistaken.
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Many of the Subaru and Porsche manual transmissions share the same layout and issues as the Corvair (synchro-transaxle w hypoid). Widmans paper goes over this application in detail.
http://www.widman.biz/Corvair/English/Links/Transaxle.html
My recommendation would be the Red Line 75W90 NS (is there an Amsoil equivalent?) or the super-flowing Motul Gear 300 75w90. Both of these specifically mention compatibility/performance with synchros.
http://www.widman.biz/Corvair/English/Links/Transaxle.html
My recommendation would be the Red Line 75W90 NS (is there an Amsoil equivalent?) or the super-flowing Motul Gear 300 75w90. Both of these specifically mention compatibility/performance with synchros.
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Originally Posted By: martinq
Originally Posted By: Bandito440
GL-5 is correct for the application.
Then the OP (VinceF) must be mistaken.
I took his original post to be a blanket statement suggesting that GL-4 is for transmissions and GL-5 is for differentials.
GL-5 75w-90 is specified for the manual transaxle of 2007 Subarus.
See Item 11-18
Originally Posted By: Bandito440
GL-5 is correct for the application.
Then the OP (VinceF) must be mistaken.
I took his original post to be a blanket statement suggesting that GL-4 is for transmissions and GL-5 is for differentials.
GL-5 75w-90 is specified for the manual transaxle of 2007 Subarus.
See Item 11-18
Originally Posted By: Bandito440
I took his original post to be a blanket statement suggesting that GL-4 is for transmissions and GL-5 is for differentials.
Same here.
Originally Posted By: Bandito440
GL-5 is specified for the manual transaxle of 2007 Subarus.
See Item 11-18
Bonus points for the link! Was hoping they'd have more detail listed.
I took his original post to be a blanket statement suggesting that GL-4 is for transmissions and GL-5 is for differentials.
Same here.
Originally Posted By: Bandito440
GL-5 is specified for the manual transaxle of 2007 Subarus.
See Item 11-18
Bonus points for the link! Was hoping they'd have more detail listed.
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I'm thinking of doing it myself if I can find my T-70 Torx bit somewhere.
I ran the Red Line 75W90NS for about 17K miles until I heard about the Motul Gear 300. I still have most of a liter bottle. It's been around for a while, but I think it should still be good. I bought it cheap from a motorcycle supply shop online.
The Gear 300 stayed in there for about 50K miles until my reverse broke and I got it fixed. I'm not sure what's in there now, but I'm guessing a basic 70W90 GL-5. I know a lot of people like to change the gear oil on a regular basis, but I understand that there's no change interval actually spec'ed.
I ran the Red Line 75W90NS for about 17K miles until I heard about the Motul Gear 300. I still have most of a liter bottle. It's been around for a while, but I think it should still be good. I bought it cheap from a motorcycle supply shop online.
The Gear 300 stayed in there for about 50K miles until my reverse broke and I got it fixed. I'm not sure what's in there now, but I'm guessing a basic 70W90 GL-5. I know a lot of people like to change the gear oil on a regular basis, but I understand that there's no change interval actually spec'ed.
GL-5 is specked by Subaru, and I am using their EXTRA-S. Some say it is and isn't their factor fill. Had some really hard shifting from 1-2 early on, so much so the revs would drop to idle. Read a rebuilder on line say, the trans takes about 10K mi to break in. I switched to the Extra-S about then, and the shifting improved, but had been getting easier for a few K mi, so not sure how much the oil helped. I believe Subaru said not to use Redline NS when I asked. Service mgr and some others say that the oil has to get pretty hot for the sulfur to attack the yellow metal. Others say the sulfur is a type that doesn't react. Never broke a stick shift trans, and would prefer not to now. Had one that was hard shifting till warmed up when cold out, and added Slip-G to solve it. Had another that started growling when decelerating from speed. Couldn't convince the service mgr to even check the oil level. He said they All make the noise, so I checked it, and it only had 1/3 the oil. Filled it and never had a problem after.
They say, the GL-5 protects the axle, and better to protect that then the trans, and I say, Bbbbbbbbbb Sssssssss.
I got a Torx T-70 from Auto Zone for 3-4$.
They say, the GL-5 protects the axle, and better to protect that then the trans, and I say, Bbbbbbbbbb Sssssssss.
I got a Torx T-70 from Auto Zone for 3-4$.
Originally Posted By: y_p_w
I'm thinking of doing it myself if I can find my T-70 Torx bit somewhere.
I ran the Red Line 75W90NS for about 17K miles until I heard about the Motul Gear 300. I still have most of a liter bottle. It's been around for a while, but I think it should still be good. I bought it cheap from a motorcycle supply shop online.
The Gear 300 stayed in there for about 50K miles until my reverse broke and I got it fixed. I'm not sure what's in there now, but I'm guessing a basic 70W90 GL-5. I know a lot of people like to change the gear oil on a regular basis, but I understand that there's no change interval actually spec'ed.
Got a Torx T-70 at Auto Zone for under 4$. Some said they paid 15$ somewhere.
I changed the oil 2X with the Subaru Extra S. First time had some metal on the TransAx magnetic drain plug, and the rear oil was black. Rear only takes .8 qt, while the TransAx is 3.5qts but looked brown.
I'm thinking of doing it myself if I can find my T-70 Torx bit somewhere.
I ran the Red Line 75W90NS for about 17K miles until I heard about the Motul Gear 300. I still have most of a liter bottle. It's been around for a while, but I think it should still be good. I bought it cheap from a motorcycle supply shop online.
The Gear 300 stayed in there for about 50K miles until my reverse broke and I got it fixed. I'm not sure what's in there now, but I'm guessing a basic 70W90 GL-5. I know a lot of people like to change the gear oil on a regular basis, but I understand that there's no change interval actually spec'ed.
Got a Torx T-70 at Auto Zone for under 4$. Some said they paid 15$ somewhere.
I changed the oil 2X with the Subaru Extra S. First time had some metal on the TransAx magnetic drain plug, and the rear oil was black. Rear only takes .8 qt, while the TransAx is 3.5qts but looked brown.
Originally Posted By: Sawdusted
Don't think too much about it. Use whatever the Subaru recommends.
I would not put in a GL-5 oil in a GL-4 recommended axle/transmission. GL-5 is not backward compatible with GL-4. It has different friction modifiers and can wreck a transmission especially a Nissan gearbox.
GL-5 is recommended in the TransAx by Subaru, but everyone says that 5 isn't good for the syncroes in a trans. People say its to protect the gears in the axle. In the auto the trans is isolated from the front axle, so oils are separated.
Don't think too much about it. Use whatever the Subaru recommends.
I would not put in a GL-5 oil in a GL-4 recommended axle/transmission. GL-5 is not backward compatible with GL-4. It has different friction modifiers and can wreck a transmission especially a Nissan gearbox.
GL-5 is recommended in the TransAx by Subaru, but everyone says that 5 isn't good for the syncroes in a trans. People say its to protect the gears in the axle. In the auto the trans is isolated from the front axle, so oils are separated.
I've heard that some use Mobil Delvac Synthetic 75W-90. It's generally meant for truck applications, but Mobil has said that Mobil 1 LS 75W90 is more suitable where the LSD additive is needed. It's pricey though, but probably no different than Subaru OEM or the other suggested options.
MolaKule
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I don't know if this will help, but here is another discussion of Subaru driveline components
Another Subaru Discussion
Another Subaru Discussion
Originally Posted By: y_p_w
I've heard that some use Mobil Delvac Synthetic 75W-90. It's generally meant for truck applications, but Mobil has said that Mobil 1 LS 75W90 is more suitable where the LSD additive is needed.
I don't believe that either of these are formulated for synchro engagement, unlike the Red Line 75w90 NS and MT-90.
I've heard that some use Mobil Delvac Synthetic 75W-90. It's generally meant for truck applications, but Mobil has said that Mobil 1 LS 75W90 is more suitable where the LSD additive is needed.
I don't believe that either of these are formulated for synchro engagement, unlike the Red Line 75w90 NS and MT-90.
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