The old, heavy ex-rental splitter I have has 4.80-8s on it, but NO SPRINGS! If the road was perfectly smooth, I might risk 40 MPH, but that's about all. It bounces all over the place on any bumps, forget about potholes! And that's with a BRAND NEW 2" tow coupler & safety chains on it-when I brought it home it got a ride on the trailer!