Utah Department of Transportation

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Welcome to the Utah Department of Transportation’s (UDOT) transportation information resource from the mouth of Parleys Canyon (I-80) to Park City. Follow @UDOTWasatchBack on X or Instagram/Facebook for road status updates.

UDOT TRACTION LAW //

BE READY FOR WINTER DRIVING

If you’re headed to Utah’s ski resorts, make sure you’re prepared for winter conditions and have the required traction devices for our roads.

Winter Driving Tips
Rent a Vehicle

What is the “Traction Law” and what are “Traction Devices”?

The Traction Law is Utah’s administrative rule (R20-6) that the Utah Department of Transportation (UDOT) and law enforcement implements during severe winter driving conditions. It is important to ensure that you have traction devices (snow tires, chains, snow socks, etc.) appropriate for winter driving conditions, it is the rule of the road. Traction devices are required during severe winter weather conditions on roads throughout Utah, including I-80 in Parleys Canyon, US-40 in Summit and Wasatch Counties, and Marsac Avenue (south end of SR-224) in Park City.

Parleys Canyon uses two classes of traction requirements. Travelers are notified which requirement is in place via road signs, message boards, the UDOT Traffic app, and UDOT social media.

CLASS I: only applies to vehicles over 12,000 Gross Vehicle Weight (GVW), like buses, semi-trucks, etc. 

CLASS II: ALL VEHICLES

AWD/4WD: M + S or M/S tires on all wheels is the minimum requirement. Traction devices such as chains, snow socks, etc. or 3 peak mountain snowflake (3PMSF) tires on all wheels are also acceptable and provide the most reliable traction in severe winter conditions.

2WD: 3 peak mountain snowflake (3PMSF) tires on all wheels is the minimum requirement. Traction devices such as chains, snow socks, etc. on at least two drive wheels are also acceptable.

TRACTION LAW FREQUENTLY ASKED QUESTIONS

What is the actual rule?
The current Utah Administrative rule (Rule R920-6. Traction Device/Tire Chain Requirements) states:

R920-6-4 (3)
When road surface conditions warrant, as determined by UDOT, UHP or designated local law enforcement agency, no vehicle will be allowed or permitted the use of the highway unless:
(a) For Class I Traction Segments, vehicles over 12,000 GVW shall be traction device equipped, and
(b) for Class II Traction Segments, all vehicles shall be traction device equipped or four-wheel drive as defined in this rule.

R920-6-4 (4)
Travelers are notified when traction devices are required via road signs and UDOT's traveler information systems.
What are the agency traction law responsibilities on snow days?

R920-6-5. Responsibilities

(1) The decision to require traction devices is made by UDOT, UHP or a designated local law enforcement agency. The agency deciding to require traction devices notifies the other agencies involved.

(2) UHP and/or a designated local law enforcement agency enforces the traction device requirements.

(3) UDOT communicates traction device requirements to the public.

(4) Personnel authorized to enforce this rule may permit vehicles that do not meet traction device requirements to travel a traction segment of the highway if authorized personnel believe they may do so without endangering public safety, creating a hazard, or interfering with highway maintenance operations.

So who is actually causing all these slide offs? I see an awful lot of 2WD vehicles with out of state plates heading up the canyons.
It’s true, plenty of out of state 2WD cars without traction devices make it up the canyons and slide off. However, many vehicles involved in slide offs or crashes are Utah residents who have met the criteria of the Traction Law and would have been allowed up.

Poor tire tread for snow, driver difficulty in navigating winter conditions and speed also contribute to slide offs/cashes.

It is critical that all travelers (even the locals) have confidence in their winter driving abilities. If you don’t, we recommend taking a shuttle or public transit or delaying travel until road conditions improve instead of white-knuckling it.
So who is actually causing all these slide offs? I see an awful lot of 2WD vehicles with out of state plates heading up the canyons.
It’s true, plenty of out of state 2WD cars without traction devices make it up the canyons and slide off. However, many vehicles involved in slide offs or crashes are Utah residents who have met the criteria of the Traction Law and would have been allowed up.

Poor tire tread for snow, driver difficulty in navigating winter conditions and speed also contribute to slide offs/cashes.

It is critical that all travelers (even the locals) have confidence in their winter driving abilities. If you don’t, we recommend trying out the ski bus instead of white-knuckling it.
What are 3PMSF tires?
3PMSF tires meet more stringent winter traction performance requirements and have been rated for “severe snow service.”

These tires perform better than all-season tires on snowy, slippery roads and low temperature or freezing roads. This is accomplished by a different rubber compound that provides more grip on snow and on cold pavement than an all-season tire.
What are M+S tires?
When a tire has M+S on it, that means that it meets the Rubber Manufacturers Association (RMA) guidelines for a mud and snow tire. Tires with the M+S symbol continue to be the broader definition for the minimum acceptable levels of winter traction.

The M+S rating means that a tire has better mud/snow traction than a summer tire, but the rating doesn’t reflect traction for wet, soupy mud, slush, ice, fresh snow or even cold, dry pavement.

Most all-season tires do not qualify for the 3PMSF symbol because the tread rubber in all-season and summer tires become hard at temperatures below 40 F.

WINTER DRIVING TIPS

UDOT wants you to stay safe on the roads this winter. By following these tips and advice, you’ll be ready for winter driving. And don’t forget: Ice and Snow, Take it Slow!
Winter Driving Brochure
Winter Driving Tips

WINTER DRIVING TIPS

UDOT wants you to stay safe on the roads this winter. By following these tips and advice, you’ll be ready for winter driving. And don’t forget: Ice and Snow, Take it Slow!
Winter Driving Brochure
Winter Driving Tips

RENTING A VEHICLE FOR WINTER WEATHER DRIVING

Winter weather driving is challenging. If you are visiting from out-of-town and renting a vehicle, check with the rental company to verify that your vehicle is equipped with four-wheel drive (4WD) or all-wheel drive (AWD) and the correct tires.

UDOT has partnered with Enterprise Rent-A-Car, Alamo, National and Budget out of the Salt Lake City Airport as well as Rugged Rental and Go Rentals for the UDOT Cottonwood Canyons Sticker Program to pre-inspect rental vehicle tires for the 2024/25 season. While enforcement using those stickers is only in place for the Cottonwood Canyons, the stickers indicate a vehicle is equipped to travel anywhere traction devices are required.

If you choose one of these companies to rent a vehicle during your visit to Utah, look for a vehicle with a sticker on the inside of the front windshield – this is a vehicle that has been pre-inspected and meets Utah’s traction law requirements.

Go-Rentals:

For reserving vehicles at the airport, contact Go-Rentals At Your Service at 1-800-464-8267 to get prequalified and you will be given steps on how and where to retrieve your rental vehicle at the SLC International Airport.

If you are arriving via private aircraft at any of the surrounding FBO’s, you can contact the Go-Rentals direct line at 801-893-9263, where they will enter the reservation in-house and meet you planeside upon arrival with your rental vehicle.

Budget:

If you reserve any class of SUV or pickup truck at a Budget of Utah location, customer service will help you identify a vehicle with the sticker at the time of rental. 

Enterprise, Alamo, National:

Enterprise, Alamo and National provide the ability to reserve “Guaranteed AWD” car classes on their websites. If “Guaranteed AWD” vehicles are all reserved, this option will disappear from the available vehicle list. If it is not showing as available, then all cars with stickers are already reserved.

Rugged Rental:

All Rugged Rental SUV and truck-type vehicles are within the UDOT winter regulations. In addition, anything that has *4WD* or *AWD* on the Rugged Rental website also meets the requirements of the sticker program and Utah’s traction law.

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