Low profile tires (225/40's) are problematic?

April 30, 2014 5:07 PM

Contemplated new car comes in a base version with 17" wheels & 225/45 tires. But mostly because of a single feature (better seats) I'm thinking of getting a higher end version that comes with 18" 225/40's. Are the 225/40's going to be noticeable more troublesome with respect to blowouts, rim damage etc here in New England? Sales guy claims there is little or no practical difference. I know that the 225/40's should handle better but I don't really care about that.
posted by Kevin S to Shopping (7 answers total)

I've been driving on 18'' 225/40s in NYC for the last six years. If I remembered that it annoyed me I wouldn't do it again but I'm used to the ride now. I'd guess I' ve had one flat from a pothole that may or may not have happened because of the low profile wheels. It's really the ride I dislike. Tho I also have tighter suspension.
posted by JPD at 5:26 PM on April 30, 2014

Although one thing to consider vis-a-vis snow tires: If the manufacturer takes advantage of the bigger stock rim to put bigger brakes in there, you might have a limited selection of steelie rims and snow tires to choose from.
posted by Kyol at 5:35 PM on April 30, 2014

You're looking at a sidewall height of ~90mm instead of ~100mm, so while they're on the slim side, neither of these are ultra-low profile rubber bands. They'll be relatively fine.

That said, I also live in the Northeast, and I have a set of wheels and winter tires that make life better for 1/3 of the year.
posted by grudgebgon at 5:46 PM on April 30, 2014

A few years ago in Chicago I lost five 225/40-18s to potholes and road debris over +/- a year. I don't know that it's the tires' fault, but I'd never lost a tire terminally to such things before, and didn't loose any more tires in the next year of similar Chicago driving on a similar car with 225/45-17 tires, or in the next two years of non-Chicago driving that included quite a few miles on miserably bad dirt roads.
posted by wotsac at 6:34 PM on April 30, 2014 [1 favorite]

The 18's will give a worse ride and also the sidewall stiffness inherent in that will make poor condition handling (cold rain and snow/ice) difficult. Also, on rough surfaces (so, US city roads for the most part and regional roads) the 17/45 (in general) will be less prone to losing line through surface imperfections.

I have 18" Summer tyres and 17" winter tyres. If you want to use the same wheels year round I would stick with the 17's. 18's look better, they handle better, but unless you are going to take it on a track, the average driver will never notice the difference in handling, but they WILL notice the difference in ride quality.

Also, winter tyres on 18/40's are HELLISH expensive. I got a set of wheels (alloys) *and* a full set of very good quality Michelin winter tyres for the same amount as just putting rear winter tyres on the 18" wheels would have cost me.
posted by Brockles at 6:36 PM on April 30, 2014

Second Brockles that you'll want a set of 17" (or even 16" if they clear your brakes) steel wheels or cheap factory alloys with dedicated winter tires, and then you can run summer 40-series tires on your 18s. Best of both worlds and you get the seats you like.

On my old car (B6 Audi A4 sport quattro), the difference between comparable 45-series tires on the stock 17s and 40-series on the optional 18s was very noticeable. YMMV.
posted by a halcyon day at 1:44 AM on May 1, 2014

Response by poster: Thanks everyone. Pretty much corroborates my impression that the 40's would not be the end of the world, though not preferable.
posted by Kevin S at 3:54 PM on May 1, 2014