Better to have used oil too thick than too thin and in practical terms there probably isn't much difference as different brands vary slightly in the exact viscosity at the same stated grade. In service the actual viscosity will change up and down with it getting thinner as it gets diluted with diesel from DPF regeneration and getting thicker as the soot load builds up. 2012 TDV8 Vogue (L322)

Is a whole lot better now with the correct oil!

Thanks for the advice Fuji White 2011, 4.4 TDV8 Vogue SE