Yes 18's will fit with no problems. 17's have problems clearing the brake rotors.
It probably isn't a function of the size of the tire as much as the type of tire itself. The Fortera tire seems to be a "jack of all trades" tire, with no specific strength or weakness. Switching to a tire with more focused winter performance (maybe even dedicated snow tire) will gain you the most traction in winter weather. Going from the 20" to an 18" will help the tire grab a little better because a taller sidewall can conform to countours of the road easier, but that change is minimal.I just drove my '14 Diesel Overland with the OEM 20" Fortera M&S tires, up to our house in the mountains through sleet, snow and freezing rain. It does seem like my '07 limited with 18s was maybe a bit stickier in the slush. Do 18s really give you more traction in the slop ? And why ?
Are 18-inch tires good in snow?I have a 2015 JGC with 3.0 diesel. I live in rocky mountain area. I found that my 20 inch tire are about 9-10 inches wide. When driving on slush 2-3" deep that they will climb up on top of the slush. If you go over 30 mph or so you lose control of most of you steering. All of us older folks that drive in mountains on ice, snow or mud, know the narrower tire the better control and the better traction you have. In fact with wide tire you will have trouble getting around in the hill when muddy. They are very dangerous on ice and mud. Also they will hydroplane much easier. Now on the other hand if you are in sand it is just the other way. So why do our Jeeps come out with wide tire, racing slicks??
Also when going down the highway at speed the wider tires catch more wind causing your mileage to go down a little.
Can I get a 20" tire that is narrower?
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