Dynamic drop down based on another drop down input/selection

On my form, I have a drop down list with five various vehicle types. Based on what is selected, I want to create another drop down that will provide the models that could be selected. For example, if one selected Auto, the drop down would display Compact, Sedan, Hybrid. But if selected Truck, the drop down would display Standard Cab, Extend Cab, etc. and not the Auto selections. This second drop down should be able to display the selections from the first answer, thus always changing based on what is answered in the first drop down. I was thinking this could be completed within the workflow settings, but not sure. Still new to Nintex.