The speed limit is 55 mph on gravel, loose dirt, or on loose surface highways and on paved two-lane county and township highways if there is no speed limit posted.

The speed limit is 65 mph on two-lane highways if posted for that speed.

The speed limit is 70 mph on paved four-lane divided highways.

The speed limit is 75 mph on the interstate (I-29 and I-94).