Gear box oil??

[Craig_B]

I was changing the fluids in my new to me Argo. 1983 Argo TB 8x8

Used my fluid evacuator to remove the gear oil from the gearbox.
The manual says to use 80W90 gear oil.

I had some of this gear oil that I had for the outdrive on my boat.



Says its Full Synthetic but does not list the viscosity on the bottle and I cannot even find it on the internet.
Does anyone know if this would work?

Hope so Because its already in there. lol

[glen1971]

Is this what you put in? It is 75W90.

https://www.westmarine.com/buy/sierra--high-performance-synthetic-blend-lower-unit-gear-lube--2314227

[curtisbyrne]

i would go with the recommended oil (80W90) just because it states that you should use that gear oil,i like to think that if it dont matter what you use when it comes to engine/tranny oil it wont tell you what specifically to use....in this case it asks for 80w90 use it!

[Craig_B]

I agree always use the proper lubricant.
The reason I ask is according to the Mercruiser manual the outdrive takes 80W90.
So if this fluid works in the outdrive it should work in other components that also require 80W90.
My only hesitation is that the bottle does not state its viscosity.

[Craig_B]

I finally found the specs myself. It is . 75W90
Which means it will work perfectly. Especially during the winter.