I have a 2004 dodge ram 1500pick up with the 3.9ltr engine. What other vehicle has the same motor that would work in my tfuck

My advice would be to consult a local salvage yard / used parts supplier (like LKQ or similar) who has the ability to cross reference and share with you what motors will work in your RAM. My rule of thumb is: stick with the same year and model for best results.