The speed limit for trucks in CA is 55mph statewide. Doesn't seem to be that big an issue.
(It's not an exaggeration because there seem to be about 2 state patrol cars and they're always parked at Walmart getting coffee. If you want to drive 100 as private passenger vehicle, go right ahead. If you want to drive 85 with a rig full of cows, feel free. While Nevada and Montana lost their no speed limit statuses due to federal funding and regulations, but worked around it by issuing smaller penalties.)