Hi All,

I want to run synthetic oil in my gear boxes... I know Yami recommends SAE 80 GL-4 Hypoid gear oil. For 2008 (though I own a 2007) the operator manuals say that SAE 80W90 Hypoid gear oil can be used..

My brief internet searching only came up with the following and I'd like to use a known name so I found:

Synthetic:
Mobil 1 75W90
Castrol Syntec 75W90

Non-Syn:
Castrol Hypoy C 80W90

Any of the 3 should be good enough? Anyones thoughts?

 

<div class="FTQUOTE"><begin quote>Originally posted by: CraZySteve

Hi All,



I want to run synthetic oil in my gear boxes... I know Yami recommends SAE 80 GL-4 Hypoid gear oil. For 2008 (though I own a 2007) the operator manuals say that SAE 80W90 Hypoid gear oil can be used..



My brief internet searching only came up with the following and I'd like to use a known name so I found:



Synthetic:

Mobil 1 75W90

Castrol Syntec 75W90



Non-Syn:

Castrol Hypoy C 80W90



Any of the 3 should be good enough? Anyones thoughts?</end quote></div>

any of them should be fine. Yamaha will recomend one thing, then someone else will recomend something else, they should all be fine.
But hell I run striaght 90w in my bigbear and it does just fine.

 

I always use Synthetic Castrol but In my 650 H1 I put Lucas 75-90 Synthetic which is hypoid also. Suppose to be excellant. Any synthetic is better than normal gear oil, atleast in my opinion..