Can I return a used truck that keeps breaking down after having it 3 weeks?

by Dawn
(Missouri)

My husband traded in our 2009 international prostar with a cumin isx for a 2006 kenworth t600 with a c13 because of all of the repairs on the dpf.

So we went to Quality truck sales in Springfield Mo. First week out we had to replace the axuater and a water pump and little oil on the engine.

Now we are having power problems and oil All over the engine. This started on the third week we have had it. My question is is there a law in Missouri that allows us to return or replace the truck?

Btw..The truck has a 4 yr unlimited mile warranty but only what they replaced.

Thank you for any answers you have.