Amount of Sidewall on TV tires.

[love2tow]

I have read through many of the topics regarding tires on this forum but I can't find much as it relates to the size of the sidewall. How much sidewall is too much?
The tires I have on my truck now look small. I would like to fill out the wheel wells a little more without having to buy 18 or 20 inch wheels.

On my 2012 F250, I have 245/75/17. The next size up is 265/70/17. Those are my two OEM options. The 245's have 7.23 inches of sidewall and the 265's have 7.3 inches.

Now, I used a conversion calculator and tried finding tires that were close to the same diameter of the 20 inch OEM size of 275/65/20. What I came up with was 285/75/17 and 285/70/17. They have a sidewall of 8.42 inches and 7.85 inches respectively. I'm just concerned that adding an inch of sidewall will cause additional flex and a lack of stability. I want the truck to look a little better but don't want to impact safety while towing.

Any Advice?

[blt2ski]

Going from current tire to options.al tire reduces,es effective ratio from about a 3.55 to 3.3-3.4 or there abouts. This can be both good and bad depending upon how you use the truck et,.

Marty

[love2tow]

Slated4Greatness wrote:
Also keep in mind that you will be effectively numerically lowering your gear ratio. Starting at 3.55 with stock size and ending at 3.40 etc. THe 3.40 is not an exact # but a showing of what I mean by "lowering".

Very true. After looking more and more into this, I'm realizing that it may be in my best interest find an all terrain tire in the stock size and save the modifications for my ATV :B

[Slated4Greatnes]

Also keep in mind that you will be effectively numerically lowering your gear ratio. Starting at 3.55 with stock size and ending at 3.40 etc. THe 3.40 is not an exact # but a showing of what I mean by "lowering".

[love2tow]

The unfortunate thing about the 2011 and beyond super duty trucks is that they come pre-programmed with 6 or 7 sizes of rim/tire and the ability to adjust it by rev's per mile is gone. I can't find a tire that has the diameter of the 275-65-20. The closest I can get is 285-75-17 and can only get Nitto Terra Grapplers or BFG Mud Terrain in that size.

And what is the next load range? G?

[easycamper]

If you go up in load range as well as in size, you should get a stiffer sidewall that would counteract the increased tendency for sway/instability.

Or, you could lower the truck 🙂

[BenK]

Sidewall is only one component of it for towing

In the early days of over sized dia wheels (folks here used to laugh at
them as low rider types) and low profiles (low aspect ratio)...the tire
offerings did NOT support LT class very well.

What there were, were mainly from OEMs and tough if not impossible to
find replacements from independent (non dealer) tire shops

Today's offerings do have decent LT class tires of higher load ratings.
So your question and answer is almost a mute point as long as you stick
to the proper load range for 'your' TV's ratings needs

You have a +8K GVWR, so OEM spec'd 'LT' class tires

So stick with LT class and of the min load rating according to your
drivers door label

Going over sized will dictate either reprograming the tire rev's per
mile for the computer's look up tables, or just living with the speedo
being off.

Torque-management of the tranny will an an issue if you don't change
the look up tables to the correct rev's per mile (tire OD)

Just stick to the OD of the OEM tire for your vehicle and the re-engineering
of the over sized tires will have the tire engineers bake in the metrics
for sidewall strength...unless you like to do the re-engineering...