Pterodactyl_imp said:
Hiker, what about the chart and note on the left? Maybe that's just there for decoration?

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Cheers
Put your lawyer hat on (I'm not a lawyer): "Other viscosities shown in the chart may be used....."
So, if you happen to have some 10W-40 kicking around the garage, *and* your ambient temperature is 60F or more, it's OK to use it.
But the recommended oil viscosity is 10W-30

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