F350 dually can I use acorn nuts as my lug nuts like the 18 wheeler style

 

if the wheels are designed for them Yes
Like the ones on my truck.
If factory Alcoa then no they take a flat washer style
I do beleave

 

I'm not sure how to determine if there designed for them or not I just have the factory steel wheels

 

The difference is whether the rim has a flat face or an angled seat for the nut to seat into. You'll just have to look at the rims and see if the surface is flat around the lug hole (requiring a nut with a washer on it) or beveled.