Picked up a 6’ x 12’ trailer today to haul some stuff from my dad’s house from Arizona to Ohio. Along the way here to Arizona we noticed some going considerably faster than the 55 MPH speed limit painted on the fender and in my rental agreement. Well, the 4 tires are rated for 81 MPH, and appear to be in good condition. Also not loading it heavily, under 1000 pounds. So, would 70 be reasonable? It would take us a bit longer at 55 as well as annoying the heck out of every one else in TX and NM with a 75 speed limit on I-40.