I'd personally like to see the code that says one can not run over the speed rating for a tire! At least here in Wa st, the LEO's do not care if you are over a door placard wt, much less a speed rating! You just have to be under your paid for registration tonnage!
Then again, ANYWHERE in Wa st, which is where I am assuming old man was driving, if you are pulling a trailer, or have a rig with a gvwr, or the total of the truck and trailer is over 10K, you max speed is 60 mph! So the speed rating of a tire is really a non issue per say!
Marty