A single unit vehicle or any vehicle in combination may not be equipped with more than four axles unless the additional axles are steerable, castering, or pivoting axles.
N.D. Cent. Code § 39-21-54
Requirement for steerable, castering, or pivoting axles
Official source: North Dakota Legislative Branch. Reproduced from public-domain North Dakota statutes; confirm against the official source for the current text. Not legal advice.