2001 3.0L Fluids Question

I just bought a 2001 Taurus for my daughter. I read the owners manual. It says I need ATF to be Mercon V. However the Haynes Manual says just Mercon. If I change the ATF or schedule or before is the Mercon going to do what is needed? Or would I be better off staying with Mercon V?

Also, the owners manual says to use 5w20 motor oil. Haynes says 10w30. Which is right?

The only real reason for these questions is the price difference of the fluids.

Thanks,
Russell

Use only Mercon V xmsn oil in vehicle.
You can use 10w-30 okay. 5w-20 was used only to help Ford meet over all product fuel mileage standards.