Kansas Studded Tires: Legal November 1 to April 15, and Two Different End Dates

The Kansas rule sits in two layers, and reading only the first one gives the wrong answer. K.S.A. 8-1742(c) makes it unlawful for a tire on a highway to carry any protuberance projecting beyond the tread, then lists four exceptions: farm machinery, tire chains, studded traction equipment, and pneumatic tires with metallic or nonmetallic studs. For the last two the statute adds a condition the first two do not carry: they must be approved by the secretary of transportation by adoption of rules and regulations, and their use may be limited to certain months or types of vehicles by those rules. So the Kansas statute contains no dates whatsoever. Anyone quoting a Kansas studded-tire season from Chapter 8 alone is quoting something that is not there.

The dates live in Kansas Department of Transportation regulations, Agency 36 Article 7, which the Secretary of State's rules portal still lists as effective. K.A.R. 36-7-1 K covers a stud tire, meaning a tire the manufacturer built with studs seated in pre-molded holes: no stud tire may be used on a public highway earlier than November 1st or later than April 15 of any winter season. K.A.R. 36-7-2(d) covers studded traction equipment, meaning a device attached or placed onto an ordinary tire to add bite: that equipment is permissible on Kansas highways on and after November 1 of each year to and including April 1 of the succeeding year. Two official Kansas instruments, adopted 21 years apart, therefore end the season two weeks apart. The narrower rule is the April 1 one, and it applies to the strap-on or clamp-on device rather than to the studded tire itself, so a driver running factory stud tires has the longer window.

The same regulations set the hardware limits. A stud's tungsten tip must project not less than .040 inch and not more than .090 inch above the tread surface, measured on tires before use and re-measurable after 10 miles at up to 50 mph. A passenger-car stud tire must carry between 60 and 150 studs, the stud body may not exceed .400 inch in diameter including its casing, and at least 2/32 inch of rubber must sit between the base of the stud and the cord body. K.A.R. 36-7-1 J confines studs to single-tire passenger vehicles and other single passenger vehicles rated up to and including 3/4 ton, so a dual-wheel pickup is outside the allowance. Bolt-on studded traction equipment must carry a minimum of 32 studs per device and must reach across the tread at intervals of not less than twelve inches around the circumference.

Approval is a manufacturer duty, not a driver duty. Under K.A.R. 36-7-1 the maker or retreader applies by letter to the traffic and safety department of the state highway commission in Topeka and may receive a provisional certificate of approval; under K.A.R. 36-7-2(f) a maker of studded traction equipment applies in writing to the secretary of the Kansas Department of Transportation, which may demand sample pairs and may deny a certificate outright. A Kansas driver buying an approved product does not file anything.

Tire chains are the outlier worth knowing. K.S.A. 8-1742(c)(2) permits tire chains of reasonable proportions upon any vehicle when required for safety because of snow, ice or other conditions tending to cause a vehicle to skid. The approval-and-months sentence in the statute reaches only paragraphs (3) and (4), so chains need no KDOT certificate and are not confined to the winter months at all: the trigger is the road condition, not the calendar.

Running studs outside the regulatory season is charged as improper tires under K.S.A. 8-1742, which the uniform fine schedule at K.S.A. 8-2118(c) prices at $45 plus court costs. It is a traffic infraction, so a driver may plead and pay by mail before the appearance date under K.S.A. 8-2118(b) rather than appear, and the $45 caps only that mailed-in disposition; a court appearance can carry a larger fine. The fine doubles in a posted road construction zone or school zone under K.S.A. 8-2118. Separately, K.S.A. 8-1742(e) makes it unlawful to operate on tires that are unsafe for other reasons, including tread depth under 1/16 inch measured in two adjacent grooves, exposed ply or cord, or a tire marked not for highway use.