Tallest tire possible

[djjsc]

Have a 2008 Fusion SE V6.   Current installed tire is OEM spec 205/60R16.   Looking for more winter driving clearance.   Looking at 205/70R16s.   Anyone see any issues?

[bbf2530]

5 hours ago, djjsc said:

Have a 2008 Fusion SE V6.   Current installed tire is OEM spec 205/60R16.   Looking for more winter driving clearance.   Looking at 205/70R16s.   Anyone see any issues?

 

Hi djjsc. Are you looking for ground clearance for snow? You are probably not going to get the results you may think.  So first, you can use this tire size calculator to determine the extra "clearance" you will get: https://tiresize.com/calculator/

 

Essentially, your factory tries are 25.7" diameter/tall. And the 205/70-16's would be 27.3" diameter/tall. But that is unloaded height/diameter.

 

However...First you have to keep in mind that only half of that ~1.8" of added tire height (actually less) will result in increased ground "clearance". That means ~0.9".

Then the actual added ground "clearance" will be even less, since the weight of the vehicle will be compressing the tire sidewall. An educated guess? You may get ~0.5" of additional ground clearance when all is said and done. If you are lucky.

 

And yes, it is possible they may rub, since there is not a lot of room between the tire and suspension pieces up under the wheel well.

 

Seems like not much return on the money spent.

 

My recommendation would be to stick with the factory tire size.

 

Good luck with whatever you decide to do, and let us know how you make out.

[djjsc]

Thanks for comment.   Am well aware of the math.   Once had an '89 Civic; OEM tire was 175/70R13, no end of difficulty in snow.   Went to a 175/80R13, world of difference in winter & dare I say, smoother in summer too.

[bbf2530]

53 minutes ago, djjsc said:

Thanks for comment.   Am well aware of the math.   Once had an '89 Civic; OEM tire was 175/70R13, no end of difficulty in snow.   Went to a 175/80R13, world of difference in winter & dare I say, smoother in summer too.

 

Hi djjsc. That example would be a matter of differences due to a combination of factors...including tire make, model, tread type, tread depth/tire age, rubber composition etc.

It is the tread type, tread depth, tire width and rubber composition that matters in the snow, not the height of the tire sidewall.

The same amount of tread is in contact with the snow/ground for a 205/60/16 and a 205/70-17 tire. So the height of the sidewall makes no difference in apples to apples comparisons of tire type. 

 

As far as smoother ride: Yes, apples to apples, a taller sidewall will always give a "smoother" ride. More sidewall equals more cushioning of road imperfections.

 

But nevertheless, there is not a lot of room in the top of the wheel-well for a taller tire. Especially at full suspension compression. So I would advise against it.

 

Let us know how you make out and good luck.

Edited April 4, 2022 by bbf2530

[djjsc]

For winter driving here in Canada clearance counts at least as much as "tire make, model, tread type, tread depth/tire age, rubber composition" combined.   A vehicle w/o enough clearance underneath soon goes nowhere; at best responds erratically to steering input.   Which is why there's vehicles in the ditch EVERY first snow of the season.

[bbf2530]

1 hour ago, djjsc said:

For winter driving here in Canada clearance counts at least as much as "tire make, model, tread type, tread depth/tire age, rubber composition" combined.   A vehicle w/o enough clearance underneath soon goes nowhere; at best responds erratically to steering input.   Which is why there's vehicles in the ditch EVERY first snow of the season.

 

Hi djjsc. lol...Quite familiar with snow. Lots of it in the winter where I drive. Concerning the tires/suspension components, "clearance" is also important in the wheel-wells. And as mentioned previously, a 205/70-16 tire will cause clearance issues with the suspension, especially during steering/suspension compression.

 

The following expert site would be a good place to find some excellent information on the facts about what is actually important for winter/snow driving...according to the experts: https://www.tirerack.com/tires/tiretech/tiretech.jsp?tab=All

Scroll down to the "Winter Snow/Tires, Winter Tire Information" section for a lot of great information.

 

Good luck with whatever you decide to do.

Edited April 5, 2022 by bbf2530

[Waldo]

There are two tight areas around the front wheel in a 1st gen Fusion.  1 is the between the top of the tire and the ball joint stud on the upper control arm.  The second is when you turn the steering wheel one full turn in either direction.  The tire on the inside of the turn gets very close to the flange that joins the firewall to the body side (you can't see the flange, it's behind the plastic wheel liner, but if you rub through the wheel liner, the tire will be scrapping on metal).  So you can take a look and see if you feel comfortable with those dimensions.  But keep in mind tire math is not as simple as the numbers printed on the sidewall.  Those numbers are just "guidelines" and actual tire dimensions can vary significantly.  The manufacturing guidelines for tires are so broad that you could in theory produce a tire labelled a 205/60 and it would actually be taller than a tire that is labelled a 205/70.  And then combined with the spring rate of the tire which will determine the compressed height, you may or may not get any noticeable difference in ground clearance with a tire size change.