Are tire chains on a Prius Prime okay?

If they fit loose, they will likely slap the wheel wells.

I live in Maine. I have studded snow tires on my Pruii, in accordance with our laws here I run studded tires from October to April every winter.

 

In the Owner’s Manual (PDF), see the “Winter driving tips” section, pages 507–510, for advice on tire chains. Toyota recommends to “Install tire chains on the front tires only.”

Toyota has videos (in Japanese) showing tire chain installation and removal and storage, both using a fourth-generation Prius car as the example. I can’t imagine they would have used this model if it were unsafe.

 

Like Maine, California allows but does not require studs, though has a bit shorter permitted window. While California doesn't require any form of winter tires for driving on unposted roads, I'm seeing conflicting claims about whether not Maine has a winter tire (not necessarily studded) requirement. I do see that a mandatory snow tire law was filed in the legislature in 2019, but was quickly withdrawn.

California does not allow studs in lieu of chains:
Truck Chain Requirements | Caltrans

"What are the dates for studded snow tires?

Studded snow tires are permitted in California from November 1 until April 30 each year. During this time, studded tires are permitted in any location within the state. Studded snow tires are not considered tire traction devices and may not be used in lieu of chains.

If I have 4-wheel-drive, do I need to carry chains?

Yes. ...

If I have snow tires, do I need to carry chains?

Yes. Even though weather conditions may not warrant the use of chains on passenger vehicles equipped with snow tires at a particular time, to enter a chain control area, you must have a set of chains (one pair) for your vehicle in your possession. If conditions worsen or you have trouble controlling your vehicle, you must stop and install the chains. ...

If I have studded snow tires, do I need to carry chains?

Yes. Studded snow tires are not considered tire traction devices and may not be used in lieu of chains. ...

The manufacturer of my vehicle recommends that chains not be installed on it. Do I still have to put on chains?

Yes. Many vehicles which will not accommodate conventional link-type chains will accommodate cable chains or other devices such as “Spikes Spider.” If your vehicle is not equipped with some type of tire traction device, it is neither safe nor lawful for you to enter a chain control area. If you choose not to install tire traction devices on your vehicle, you may not enter a chain control area."

Never mind Subaru's recommendation to not use chains, my state also requires me to carry them to show to any officer or DOT employee who asks. So I do carry a set of low-clearance cable chains of the right size, that do fit, though I have never driven on them. The state nearly always closes the roads before requiring AWDs to chain up.

Since my Prius isn't ever driven into chain requirement zones, it carries an older set from a prior vehicle that fits a loose wheel, but hasn't been test fit on a wheel while mounted on the car.

 

California doesn't seem to provide much guidance for what chain alternatives are approved:

https://autosock.us/wp-content/uploads/2016/02/CHPTraction.pdf

My state does provide a bit more guidance:

http://www.wsp.wa.gov/traveler/images/traction/alt_traction_device.pdf

See Colorado too:

 

@fuzzy1 is correct. There is no requirement for winter tire (studded or studless) use in the state of Maine. From October 2, through April 30, studded snow tires are permitted on Maine roads. However, like many other states, there is a law prohibiting the use of studded tires outside of the permitted period.
Title 29-A, §1919: Studded tires - Maine Legislature
AFAIK, there is no tire chain use requirement either, but the studded tire use prohibition applies to any "vehicle with tires having metal studs, wires, spikes or other metal protruding from the tire tread", thus tire chain use is permitted (not required) from October 2 through April 30 and its use is prohibited from May 1 to October 1.

Personally, I have never used tire chains on any of my cars and have never been at a location in or out of state that requires tire chains, so I have no idea about chain use on a car.

 

In practice, the highway patrol tends to close California roads about 5 minutes after posting a chain requirement. This is deliberate, knowing that most people need at least 10 minutes to deploy their chains.

When things are bad enough for chains, they really don't want you on the road at all.

 

I'm assuming the clearance discussed here is the gap between tire and wheel well, not ground clearance.

 

The most critical measurement is from the tire sidewall to the spring perch on the strut. That's the most likely pinch point for the vast majority of chains or cables on modern cars. The gap is 12-16mm in most typical applications.

 

I just ordered Autosocks for the Camry. I understand they are considered a chain alternative in some states. Snow is generally quickly cleared here. These are for if I get kept caught out in a storm, which might happen once a year.

For the OP, since you have the chains, you can test them on the driveway. Just put them on; one whell is probably good enough. Check the clearance behind the wheel, and maybe roll the car a few feet. It's a good idea to practice putting them on before doing so in a storm.

 

At my single chain checkpoint experience on I-80, in my first Subaru, everyone ahead was turned back, but we were quickly waved through, nevermind not having the right tires on for the unseasonably early snow. While obtaining lodging in Truckee, for skiing Boreal the next day (we just barely missed skiing on Halloween, on a rare year they are open that early), I saw only a single other vehicle going through in the next half hour.

Previously, we had to chain up rental cars to get to ski hills on the other side of Lake Tahoe, back when the rental companies would still provide chains. And the state patrol would still leave the roads open. But the last time we flew in and rented, that era seemed to be ending.

I did get a lot of real chain experience in my youth, in a rural land of erratically plowed and groomed roads. And on a farm where even an F-250 with chains on all four, still occasionally got stuck, requiring a crawler tractor to pull it out. Now that I'm 'retired', I get to pull some works shifts there again, providing refreshers. The roads are better groomed now, and vehicles more capable, but the truck and ATV used to feed animals out in the fields still need chains all around. And can still find places to get stuck.

 

The alternative traction devices with fabric parts must not be driven far on pavement either wet or dry. They will soon shred. I have AlphaTrax for my other car. They look like they'll do a good job, but with fabric straps and steel studs on the things they won't withstand pavement. The Prime has Michelin Xi3 snows which I don't think are as good as Bridgestone Blizzaks. And I have cables just in case of an ice storm.