ty

So, while the TireRack-perscribed tires for 19x8.5 wheels on the 2018 SQ5 are 255/50R19, you can use 235/55R19 tires as well (I checked with TireRack). If you do, the speedometer will be off by 0.5 mph at 70 mph, so not a bad “cost” for having a narrower, slightly wider tire that should theoretically do better in the snow.

I think I would rather take the additional traction on ice and frozen street 255 than the added benefit of going through a deep snow 235. But it’s great to know the options thanks for the post

Sorry how do narrower tires have better traction? If we are speaking what tire is better for going through deep snow then yes narrow tire is better since lower resistance, but no narrower tire has better traction then there equal counterpart.


or am I missing something?

Why do people not read the entire article especially if they are going to quote or spread misinformation...

From your own link

“The reason for this is that traction is achieved in winter by cutting through the ice and snow. With wider tread, you're more likely to start snow plowing or floating on top of the surface instead of pushing down and through. This floating will result in loss of traction sooner than with a thinner or narrower option. A good way to picture this is imagine a pizza cutter slicing through a pizza.”

Exactly as I stated the narrower tire is only better when you go through deep snow, wider tire = wider contact more traction.

My % of driving through deep snow will be 2% versus 98% of cold ice conditions in the winter I will take the wider contact.

Please read the entire post or give people full story when trying to help others.

i have seen the same info but was too lazy to look and didn’t want to open this can of worms. Urban legends on tire width like these have a life of their own. One additional factor is the type of tire and tread. Studless snow vs Studded vs Mud and Snow. Then within those are the how well they perform. The difference in performance within a group often exceeds the difference between wide vs narrow. Other factors to consider are the improvements made in a tire brand since tests are last year and new compounds are introduced periodically. Another factor is different tires by the same manufacturer! For example, here are several Blizzacks with different characteristics.
I agree with you on ice being the most important factor in a winter tire. A miniscule improvement in deep snow at most might keep you from getting stuck. An Audi Quattro will probably go in deep snow until it high centers
dragging the undercarriage. But better performance if you hit a patch of black ice may save your life.
Edit: The Michelin Xi2; Haka’s and Blizzack in a studless do a good job on 20” wheels with factory 20” spec tires. I have 20” Mich. and ran them last winter-they work very well on all snow and ice, are quiet and appear to be wearing well. I have M’s on my truck and much larger tires but similar results. There may be a few feet difference in stopping distance or slight difference in traction but they get the job done well.