OK to use GL4/5 when GL5 spec'd

[Sawbones]

Hi everyone. I have a new to me 2018 BMW R1200RT and I want to replace the fluid in the final drive. I ordered some Liqui Moly 75w90 GL5 (2048) hypoid gear oil without limited slip modifiers as spec'd by BMW. What showed up from Amazon was Liqui Moly GL4/5 (22090). I would like to know if this is safe to use in my final drive. I have searched here and most of the threads ask whether GL4/5 is fine to use when GL4 is spec'd rather than my situation where GL5 is required.

If not, are their any better options? It seems like the options are pretty limited.

Thanks

 

[ripcord]

Yes, dual spec'ed gear oil is safe to use where either GL4 or GL5 is called for. The GL4 rating indicates that it is safe to use where brass or bronze components are present which not something you need to worry about with your bike's final drive.

 

[Ausfahrt]

I have been using Redline Shockproof in the final drive of my BMW R1200GSA and I love it. It runs 10-20 degrees cooler than before according to my IR thermometer gun.

 

[Sawbones]

Thanks for the replies!

 

[kschachn]

Here are a few previous threads which may be helpful:

https://bobistheoilguy.com/forums/threads/gear-oils-that-claim-gl-4-gl-5.325829/
https://bobistheoilguy.com/forums/threads/gl-4-gl-5-gear-oils-a-compromise.324560/
https://bobistheoilguy.com/forums/threads/gl-4-gl-5.40367/
https://bobistheoilguy.com/forums/threads/gl4-and-gl5-fluid-is-this-a-myth.38625/
https://bobistheoilguy.com/forums/threads/dual-gl4-and-gl5-when-requirement-gl4-manual-trans.346975/
https://bobistheoilguy.com/forums/threads/what-is-gl-4.39705/

 

[BusyLittleShop]

75W90 gear oil viscosity range 12.0 to 13.3 cSt which about the same viscosity flow for a 40 grade motor oil...

Because the viscosity of gearbox and engine oils are measured on
different scales, an SAE 80 gear oil is roughly equivalent in
viscosity to an SAE 20 grade engine oil... and SAE 85 gear oil is
roughly equivalent to SAE 30 grade engine oil...

 

[kschachn]

75W90 gear oil viscosity range 12.0 to 13.3 cSt which about the same viscosity flow for a 40 grade motor oil...

Because the viscosity of gearbox and engine oils are measured on
different scales, an SAE 80 gear oil is roughly equivalent in
viscosity to an SAE 20 grade engine oil... and SAE 85 gear oil is
roughly equivalent to SAE 30 grade engine oil...

Cool, what does that have to do with API GL-4 and GL-5?

Are you advocating the OP use motor oil in his final drive?

Just what point are you making here?

 

[Overfill]

I have been using Redline Shockproof in the final drive of my BMW R1200GSA and I love it. It runs 10-20 degrees cooler than before according to my IR thermometer gun.

smurf blood or pepto?

 

[Overfill]

Hi everyone. I have a new to me 2018 BMW R1200RT and I want to replace the fluid in the final drive. I ordered some Liqui Moly 75w90 GL5 (2048) hypoid gear oil without limited slip modifiers as spec'd by BMW. What showed up from Amazon was Liqui Moly GL4/5 (22090). I would like to know if this is safe to use in my final drive. I have searched here and most of the threads ask whether GL4/5 is fine to use when GL4 is spec'd rather than my situation where GL5 is required.

If not, are their any better options? It seems like the options are pretty limited.

Thanks

Relatable thread:
https://bobistheoilguy.com/forums/threads/honda-shadow-differential.381279/