Updated October 19, 2026
What that stretch asks of a tire
From the Kanata ramps to the core, Highway 417 is open, often above the worst of the side-street snow, and still glazed between the wheel tracks. Traffic runs at highway speed as soon as a lane looks clear. The tire has to cut slush at 100 km/h and then hold a lane change on the packed strip beside the tracks. That is a winter-tire job, not an all-season one. The comparison is in all-weather versus a winter set.
Crosswinds on the exposed sections tug a car that is already floating in slush. Low pressure makes that worse. Set cold pressure to the placard in the driveway, not after the tires have heated up on the highway.
The set to put on the car
- Four identical 3PMSF winter tires. Do not leave the rear on all-seasons.
- Tread deep enough for slush. Shallow tread packs with snow and rides up on top of it. Replace before winter if you are near that point: tread and age.
- A size close to the original so the speedometer and the stability system still match. Compare any swap in the tire calculator.
- Studs are not legal for a car kept in Ottawa. The studless winter tire is the 417 tire.
Leave extra room on the first cold morning after a storm. The left lane is not clearer just because it is moving faster. It is often the lane with the polished ice.
Questions
Are winter tires worth it for a Kanata to downtown commute?
Yes. Highway 417 mixes slush, polished ice, and highway speed. That is where a dedicated winter set earns its keep over all-season tires.
Can I run winter tires on the drive wheels only for the 417?
No. Use four matching winter tires. A mixed set is unstable in a lane change.
What tire pressure should I use for a highway trip?
The driver's door placard, measured cold before you leave. Do not bleed air out because the tires look high after a drive.
Are studded tires better on the 417?
They are not allowed on a vehicle kept in Ottawa. Use a studless winter tire with the three-peak snowflake.