Hi all, I have a 2017 Eco Boost. With winter upon us, I think it's time to change my tires to ones better suited for a Mid-western winter. I currently have the original Pirelli tires on there (255/40/19). Winter tires for this size are approximately $1,165 (Blizzak's), whereas I can get 255/50/19 for approximately $700. Is this a possible change, or would the car then have issues (odometer, speedo, gearbox, Traction Control, etc.)? Any suggestions are greatly appreciated. Thanks.

 

I got the Cobb tuner so I can use it to correct all those issues for different size tires. There's an online training course to learn how to do that, and it cost about $150 IIRC, and the tuner is $500. With the boost in performance, I thought that was money well spent.

 

Generally the larger diameter is good for the snow (provides a little more ground clearance) and should not be a problem for clearance in the fenders. Last time I checked, Ford actually designs these cars with enough clearance for tire chains.

The increased diameter will throw the speedometer off -- you will be going faster than the speedo says you are going -- but that is really no big deal. You can recalibrate it with a tuner, or just keep in mind that you are actually going a little faster than the speedo says. If the overall diameter of all four tires is the same, it should not affect any of the other systems, as long as you don't go too crazy with it.

Personally I think 255 is a bit too wide for a snow tire. I would go with the narrowest tires that will fit properly on the wheels. 235 is probably about right, and I think this will bring the price down quite a bit. Size the sidewall to make the overall diameter about the same or a little larger than the original tires.

Better yet, check your local Craig's List for some cheap take-off wheels to use for the winter that are a bit narrower than your current wheels; in 18" diameter if that will clear your brakes. Then you can go with relatively narrow tires with a tall sidewall.

 

I always stick with the stock tire size and go down one size. My current '17 had the Pony Package with 19's. I installed the 18's from my 2015, stock size on Mustang wheels. The tires are Continental Winter Contacts. They perform great in cold weather, below 42 degrees they come into their own. Using the Snow mode, I have had zero problems with them. Check with the local club in your area for wheels. Many owners move to Upgrade them and you can get a very good deal. I bought mine off a club member, new take offs, donated the Pirelli tires to charity and bought my tires from my dealer. They have specials every month, plus you can get any discounts from the tire manufacturer. I received an $80 credit card. Ford also include hazard coverage free. And, since the wheel and tire size are OEM, there is no problem with the Speedometer.