I am currently running 275/65/20's (34.1") on my 2017 F150 4WD XLT Sport with a 2-1/2" leveling kit and stock wheels (which I believe the are 9" wide??). I am happy with the way my truck currently sits (height wise) BUT from looking at it head on, it sits a little too narrow for my liking; and as a result I am looking to increase the tire width and get as close to the outside of my fenders as possible (without having to get into wheel spacers and/or suspension lift but if I have to get into spacers it's not the end of the world). How much of a bigger tire can I fit (without trimming / rubbing) before I have to start looking into a suspension lift (or am I at my max already)? Ideally I would like to be able to run 35x12.50's or is that out of the question?? What about 295/65/20's? If I have to get into wheel spacers, it's not the end of the world; however I would like to keep the spacing to as much of a minimum as possible in order to avoid any undo stress on the joints / arms / etc).

Also, how much of a disadvantage would I be putting myself at with regard to driving / traction in the snow with tires wider than I have now; considering the lighter body weight due to the aluminum body? Or is this a non-factor?

Thanks in advance!

 

2wd or 4wd?

 

4WD

 

I ran 285/65/20 with only Fox 2.5 coilovers with no issues. 2014 lariat.

My awesome 2014 lariat 285/65/20 Nitto EXO grapplers, Fox 2.5 coilovers and shocks. Only 30k miles when I traded it in on new Explorer. Big mistake.

 

Increasing the tire width won't really make a dramatic change in width/stance.

Figure if you have a 275mm wide tire now and you increase to a 305mm tire, you have increased the width by just over an inch. The outside is only going to stick out about 1/2" more than it does now. Are you looking for a pretty wide tire to gain only 1/2" of extra width appearance?

As for biggest, you just adjust to a shorter sidewall percentage to maintain a similar overall diameter....taking into consideration the wider tire may not be able to be as tall due to new interference.

Your door sticker should indicate the wheel width as long as it is the wheel that came stock on your truck. The offset is +44, probably 8.5" wide. You can search Google with a bunch of results for wheel calculators. Input your current tire size with a wheel size of 8.5" x 20" x +44 offset, then change your tire size only as a comparison to look at how small of a change the tire width will change the appearance. Maybe that extra 1/2" is what you're looking for......

 

Like above, a wider tire is not going to net you that much of a change in stance. If you truly want a wide stance with the tires sticking just inside/outside the wheel well, you'll need to invest in wheel spacers for stock wheels, or purchase aftermarket wheels with an offset of around +20mm. IIRC the stock wheels offset is +44mm. That being said, if you decrease your offset, or add spacers, you will not be able to run a tire as large as you could on stock wheels before rubbing. Those with +20mm offset wheels typically stick to tires around the 33" size for that reason. 34" tires are pushing the limits and will rub with little positive offset. 12.50" tires also run the possibility of rubbing the upper control arms if using the stock wheels and no spacers.

I run 285/65R20 tires on a 2.25" level on stock wheels and no spacers. The tires measure to 34.6"x11.5" and do not rub in any direction and motion. If I were to add a 1.25" spacer to the wheels or run an aftermarket wheel with +20mm offset I would rub severely on the crash bars and wheel liner.

 

I've got plenty of room left with 34s on a 18x9,+20 wheel. 295/7r18 Ridge Grapplers. And I have less height on my level than both of you.

 

That is just what I have witnessed. My neighbor has a 1.76" Bilstein level with 275/65R20 Ridge Grapplers (34"x11") on wheels with +20mm offset, and he rubs every time in reverse and full lock. He also rubs while turning offroad; also on a 4wd truck. Same for another hobbyist who sold his 35x12.5R18 Toyos because they were rubbing severely with aftermarket wheels and 2" level, had to size down to 305/65. Again, these are guys to who use their trucks for more than road use.

 

Strange. I only rub in one specific case and that's in reverse with steering locked to the right (so backing up left). Still have room for articulation.

In any case, seems like this one can be chalked up to manufacturing variances between individual vehicles.

 

nice looking truck.
OP, if you are looking for a wider stance, wheel spacers are the way to go. you could always put wider tires on but as said won´t make a noticable difference unless you jump up several sizes, like 305 or 315s