Which Oil Fiat Ducato?

Engine Oil: Pro-Tech 5W-30.

What oil should I put in a Fiat Ducato?

5w-30(9)

What oil do I need for my motorhome?

The viscosity you choose will depend on the climate in which you will be operating your vehicle. If you know things will be warm and won't be dropping below freezing, a 15W-30 is fine. But if you expect it may drop, or are unsure, 5W-30 or even 0W-30 might be the better choice.