Hey guys,<br /><br />I am changing my gear oil on my Yamaha 25hp 4-strk and can't figure out what to use, so I need some assistance from you folks...<br />My book says:"Hypoid gear oil(sae90)" and that's all it says.<br />Everything I have read or looked at in the store doesn't mention "Hypoid".<br />Most everything I see is 80w-90,75w-90, and so on. Does the weight matter?<br />I would like to use the best if I can buy it close by.<br />I was thinking of Mobil synthetic.<br />I will even order online.<br />Please help if you can.<br /><br />Thank you all in advance,<br />Scott B.
