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warwick-steve
Jedi Hopeful
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Hi all
Just wanted to check if Comma 80/90 GL4 oil is OK for the rear axle in a BT7?
Thanks
Steve
Just wanted to check if Comma 80/90 GL4 oil is OK for the rear axle in a BT7?
Thanks
Steve
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Oil for rear axle?
- Thread starter warwick-steve
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Steve--
I do not pretend to understand the technical difference between GL4 and GL5 oils but do know that differentials place tremendous loads upon lubricants which is why you will see words such as "Extreme Pressure" etc. in differential oil names, etc. I'm sure someone else will chime in but since there is no yellow metal in your diff there is no reason NOT to use a GL5 oil which is designed for differentials, not transmissions. The 80/90 refers to viscosity, not the oil molecules' resistance to shearing forces, and that--"High Pressure" or "Extreme Pressure" tolerance is what you are after.
I do not pretend to understand the technical difference between GL4 and GL5 oils but do know that differentials place tremendous loads upon lubricants which is why you will see words such as "Extreme Pressure" etc. in differential oil names, etc. I'm sure someone else will chime in but since there is no yellow metal in your diff there is no reason NOT to use a GL5 oil which is designed for differentials, not transmissions. The 80/90 refers to viscosity, not the oil molecules' resistance to shearing forces, and that--"High Pressure" or "Extreme Pressure" tolerance is what you are after.
OP
warwick-steve
Jedi Hopeful
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Hi Michael
Thanks for replying. I should have stated EP80-90 GL4.
Steve
Thanks for replying. I should have stated EP80-90 GL4.
Steve
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Steve--
Go here: https://www.widman.biz/uploads/Transaxle_oil.pdf
and I believe you'll see why you use a GL5 in the diff and not a GL4--and visa versa.
Go here: https://www.widman.biz/uploads/Transaxle_oil.pdf
and I believe you'll see why you use a GL5 in the diff and not a GL4--and visa versa.