Last fill was Red Line 75W-90 which seems to be a pretty standard recommendation for BMW open diffs. This time I used Amsoil Severe Gear 75W-90 since it was in an easy fill bag. Then I looked on the Amsoil site and they don't have a reccomendation for SAF-XO. Is the Severe Gear OK?
2006 BMW 530I calls for SAF-XO in the rear open diff
- Thread starter ledslinger
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I think it'll be fine, as any GL5 75w90 should do. That easy fill bag looks very handy.
https://www.amsoilcontent.com/ams/lit/g2043.pdf
https://www.amsoilcontent.com/ams/lit/g2043.pdf
KevinMalone- The bag worked awesome. If I'd have known Amsoil doesn't recommend Severe Gear for SAF-XO I may have dumped the Severe Gear into another bottle and used the bag to dispense the Red Line. I'm saving the bag for future use.
I assumed Severe Gear was equivalent for any application that Red Line 75W-90 is recommended for.
I assumed Severe Gear was equivalent for any application that Red Line 75W-90 is recommended for.
Yes, Severe Gear is ok. I use it in my car that specs SAF-XO. No problems. There is nothing special about the SAF-XO.
Castrol doesn't make SAF-XO any more, and hasn't for many years. The replacement product is called Transmax Axle Longlife 75W-90.
SAF-XO did _not_ have the friction modifiers in it that would be necessary for most clutch-type limited-slip differentials. It seemed to have been originally formulated for use in transmissions or something.
It also had a DRAMATICALLY lower Brookfield viscosity than nearly all other 75W90 GL-5 gear oils commonly marketed in the USA. Whether you need that or not is up to you and your use of the car.
Red Line used to offer 75W90NS, but I don't see it on their website now. That product also lacked the FMs for LSD use, and its Brookfield viscosity was very similar to (a bit lower than) the SAF-XO product.
BMW spec'd a lot of SAF-XO several years ago, both in their cars and in their motorcycles. I know lots of people who run something else in the bike final drives, including the Amsoil product, without incident. I wouldn't hesitate to use it, I don't suppose. Or, you can get the Transmax Axle Longlife pretty easily on Amazon.
SAF-XO did _not_ have the friction modifiers in it that would be necessary for most clutch-type limited-slip differentials. It seemed to have been originally formulated for use in transmissions or something.
It also had a DRAMATICALLY lower Brookfield viscosity than nearly all other 75W90 GL-5 gear oils commonly marketed in the USA. Whether you need that or not is up to you and your use of the car.
Red Line used to offer 75W90NS, but I don't see it on their website now. That product also lacked the FMs for LSD use, and its Brookfield viscosity was very similar to (a bit lower than) the SAF-XO product.
BMW spec'd a lot of SAF-XO several years ago, both in their cars and in their motorcycles. I know lots of people who run something else in the bike final drives, including the Amsoil product, without incident. I wouldn't hesitate to use it, I don't suppose. Or, you can get the Transmax Axle Longlife pretty easily on Amazon.
edyvw
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You are good.
