Thread: 6VD1 engine oil

Here is a little chart I made up to plot the viscosity index of some common engine oils.

The layman needs to keep in mind the engine and oil temps when running and stable, are largely constant, controlled by the coolant thermostat. If the coolant runs at 85C the oil will be somewhere between 90C and 120C.

The only big viscosity variances we see, are at the start up.... as you see below... at operating temps there is very little viscosity difference between all the grades. Having said that, if you have a range of viscosities to choose from, lean to the above average viscosity options to provide greater film thicknesses and strength. Especially so if in severe applications like pulling a plow all day.