Oklahoma Studded Tires: November 1 to April 1, Two-Ton Vehicles Only

Section 12-405(C)(1) does not begin with studs at all. It begins by banning any "block, stud, flange, cleat or spike or any other protuberance of any material other than rubber" that projects beyond the tread of a tire moved on an Oklahoma highway. Three exceptions follow: farm tractors and implements of husbandry with protuberances that will not injure the highway, tire chains of reasonable proportions when snow or ice makes them necessary for safety, and pneumatic tires with metal, porcelain or other studs. The stud exception is conditional on construction, not just on season: the tire must be built to provide resiliency on contact with the road surface, no more than three percent of the traction surface in the aggregate may be made up of studs, the studs may not project more than three-thirty-seconds of an inch past the tread, and the tire must have a rate of wear that keeps the projection within that limit.

The seasonal window and the weight limit are separate restrictions in paragraph (C)(2), and they apply to tire chains as well as to studs. Subparagraph (a) limits both to vehicles with rated capacities up to and including two tons, so a heavier truck cannot run studs in Oklahoma at any time of year. Subparagraph (b) fixes the season: a tire so equipped may not be used on a public highway earlier than November 1 of each year or later than April 1 of the following year. That is a five-month window, and it is shorter at the back end than the neighbouring plains states typically allow. Nothing in the statute lets the Department of Public Safety extend it for a late storm, and the Department publishes no separate studded-tire calendar of its own, so the statutory dates are the only official dates in Oklahoma.

Subparagraph (C)(2)(c) puts a duty on sellers rather than drivers. Copies of subsection C must be posted in every place where tires or tire chains are sold in Oklahoma, and a printed or written warning about the time limitation must be furnished to each buyer, purchaser or user by the seller of studded tires or tire chains. A shop that stocks studs and says nothing about the April 1 date is in breach of the same section its customer would be cited under.

Subsection D handles a technology the 1961 statute could not have anticipated. Operator selectable "on demand" studded tires, which carry traction-enhancing studs outside the normal tread area and switch between conventional and studded behaviour by raising or lowering tire pressure, are exempt from the subsection C prohibitions. The exemption is not unconditional. Those tires are still limited to vehicles rated at two tons or less, and the tire may not be deflated so that the studs drop and contact the road earlier than November 1 or later than April 1. In other words, Oklahoma allows the hardware on the vehicle year round but not the studs on the pavement.

Two neighbouring rules in the same section are easy to confuse with the stud rule. Subsection B bans operating any vehicle with a metal tire in contact with a hard-surfaced highway except under a special permit, and subsection E lets the Department of Public Safety and local authorities issue those permits for traction engines, tractors with movable tracks and farm machinery. Neither of those reaches passenger-car studs. Section 12-405 was last amended by Laws 2021, c. 114, Section 1, effective November 1, 2021, and that amendment left the stud window untouched.

S. Section 12-405, which sits inside the block of sections the general penalty provision reaches. S. Section 17-101(A) it is a misdemeanor to violate any provision of Title 47 not declared a felony, and Section 17-101(B)(1) sets the penalty for Sections 10-101 through 14-121 where no other penalty is provided: a fine of not less than five dollars and not more than five hundred dollars, or imprisonment for not more than ten days. A second conviction within one year carries up to twenty days, and a third or subsequent conviction within a year of the first carries up to six months, or both fine and imprisonment.

Section 17-101(D) adds that any Title 47 offense not otherwise punishable by confinement may still draw up to one day in the court's discretion, on top of the fine. Section 17-101(B)(2) lets a district attorney permit a written plea of guilty with a remittance for fine and costs where no jail sentence is mandatory, which is how most equipment citations are disposed of. Enforcement is roadside by any peace officer; Oklahoma has no periodic safety inspection lane at which stud dates or tread projection would be measured.