It depends on your usage.
Are you going to full-time or just take it out to the campground on weekends. Are you planning on crossing the Rockies or are you going to stay in the flatlands? Are you a camper or do you prefer to have your house with you?
The mid-80's trailers are light, we own one ourselves. If you don't pack your truck with the kitchen sink, you should be just fine. If you plan on carrying generators, water, gas, bikes, dogs etc then a larger truck might be an idea.