Yamaha GRIZZLY 80 2005 Manuel Du Propriétaire page 106

cC
8 In order to prevent clutch slippage (since
the engine oil also lubricates the clutch),
do not mix any chemical additives. Do not
use oils with a diesel specification of "CD"
or oils of a higher quality than specified. In
addition, do not use oils labeled "ENERGY
CONSERVING II " or higher.
8 Make sure that no foreign material enters
the crankcase.
Recommended engine oil type and quantity:
See page 10-2.
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