My son Noah and I attended a tractor show in Republic MO this weekend. Hauled two IHC Cub tractors (pictured above) and my McCormick Deering WD-40 diesel on a trailer. Gross weight was 32K. Here is a video showing pulling on to I-44 at Miami OK. The truck hits the governor at 71 MPH in 5th gear Hi.
https://www.youtube.com/watch?v=6CN_BUo0818