Changing tire size

Joined
Apr 17, 2012
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Location
West Michigan
So I'm currently running 2-2.5" of level on my F150 (Bilstein 5100 at max ride height) with LT285/70r17 tires. Looking at the next set eventually and I see that the ubiquitous BFG AT KO2's come in a couple of interesting sizes. My current tires are roughly 33.0x11.6 (manufacture spec) or so and the BFG comes in the following sizes that I am noticing
33x12.5 (32.5x12.5)
34x10.5 (approx 33.5x10.5)
285/70 (approx 32.8x11.5)
285/75 (approx 33.9x11.3)
All are 17 inch of course, with a few variables between C, D and E load ratings.

So it looks like these are some vary similar options with basically two pairs of sizes: 33x12.5 vs 285/70 and 34x10.5 vs 285/75. I would rule out the 33x12.5 because I drive on snowy highways too much for a flotation tire. I'm sure both 285 options would be great but I am curious about the 34x10.50 tire size. It is a D load rating but otherwise what makes it different from the p-metric sizes? It seems like it would be a great way to run a fairly large AT tire without going wide and sacrificing on-road snow performance. Is it made differently? IE: Will it be softer or otherwise impact on or off road performance differently than a p-metric? I was considering the 285/75r17 until I saw the 34....
 
I would take the General ATX under consideration if you're looking at the BFG's. A guy I know through truck groups runs a set on an 08 F150 in the U.P. of Michigan and has given rave reviews for them. I like them on my truck but my Missouri winters are nothing compared to you Michigan fellers.

I would go with the 285/75r17 myself. I like a tall but not crazy wide tire. I run 275/70r18 on factory suspension on my f150.

The load D bfg should suit your needs just fine as well. I just like a more common size in case of emergency replacement scenarios.
 
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You have to be very careful.

Flotation tires have the size configuration: Overall Diameter in inches X section width in inches, either a D for diagonal (bias ply) or R for radial ply , then Wheel diameter in inches, like this: 31X10.50 R 15.

Flotation tires come in Load Ranges and are built out of the same materials as LT tires - which also come in Load Ranges.

P type tires are made with a lighter fabric than LT and Flotation, because the pressures are lower. They come in Standard Load (SL) and Extra Load (XL)

If you change from an LT285/70R17 to a 34X10.50R17LT, then you should run 5 psi more. That would make the ride worse. Most other performance characteristics are going to depend more on the difference between the tires (meaning make and model) and not the size

I'm not quite sure why you want a comparison between P metric and Flotation, but the Flotation is going to ride worse. Most other performance characteristics are going to depend more on the difference between the tires (meaning make and model) and not the size.
 
You mention snow but those tires are not very good on hard pack snow and ice. It's the tread pattern, not because they're not softer winter rubber compound (though there's that too). Not all 3PMSF tires are created equal. Those with more rectangular tread pattern (more rubber contact area but with more sipes), tend to do better in winter.

I've seen Tire Rack's ratings for those and they are a joke. The KO2's should score high on off-road performance and just average in every other category. I suspect it is another case of new owners rating them compared to how their old worn out tires performed just prior to replacement, though to be fair it may only be a comparison against other similarly aggressive treaded AT tires but even then, it is trading winter for off-road performance, but that may be okay since you seem to have 4WD, except it is still pretty easy to slide off the side of an icy road.
 
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I just bought a set of 295/55/20 Nitto EXOs on Fuel 20x10's Cyclone wheels. Inflated they measured out to 12.4x32.8" Tires and wheels 128lbs.
Going on my daughter's 2018 3500 High Country. On her stock wheels (18x8s) got 285/75/18 Toyo AT2s Measured out to 11x34.8. I like those tires on long trips. Comparatively quiet and fuel efficient.
My winter set on my own truck (2011 2500 SLE Bully Dogged Duramax) are 295/65/20 Toyo CTs on the same Fuel wheel, measured out to 12.2x35.25, tires & wheels 124.5 Lbs.
The company 2017 SLE work truck got 275/70/18 Toyo CTs last week, replacing the stock 265/70/18 Michelin.

In my opinion, 16s & 17s are becoming obsolete on pickup trucks. There are 100s of used 18 & 20 inch tires and wheels for sale cheap as the lifted
truck enthusiasts move up in size.
 
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