1. The chief engineer of the state department of transportation, for good cause shown and when the public safety or public interest so justifies, shall issue special permits for vehicles or equipment exceeding the limitations on width, length, height and weight herein specified, or which are unable to maintain minimum speed limits. Such permits shall be issued only for a single trip or for a definite period, not beyond the date of expiration of the vehicle registration, and shall designate the highways and bridges which may be used pursuant to the authority of such permit.

2. The chief engineer of the state department of transportation shall upon proper application and at no charge issue a special permit to any person allowing the movement on state and federal highways of farm products between sunset and sunrise not in excess of fourteen feet in width. Special permits allowing movement of oversize loads of farm products shall allow for movement between sunset and sunrise, subject to appropriate requirements for safety lighting on the load, appropriate limits on load dimensions and appropriate consideration of high traffic density between sunset and sunrise on the route to be traveled. The chief engineer may also issue upon proper application a special permit to any person allowing the movement on the state and federal highways of concrete pump trucks or well-drillers equipment. For the purposes of this section, “farm products” shall have the same meaning as provided in section 400.9-109.

3. Rules and regulations for the issuance of special permits shall be prescribed by the state highways and transportation commission and filed with the secretary of state. No rule or portion of a rule promulgated pursuant to the authority of section 304.010 and this section shall become effective unless it has been promulgated pursuant to the provisions of chapter 536.

4. The officer in charge of the maintenance of the streets of any municipality may issue such permits for the use of the streets by such vehicles within the limits of such municipalities.

5. In order to transport manufactured homes, as defined in section 700.010, on the roads, highways, bridges and other thoroughfares within this state, only the applicable permits required by this section shall be obtained.