SUV tire size ?

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MA.
I have a 2012 Pathfinder with a stock size on my model being 245/75/16 and an optional size of 265/70/16 according to tire size calculator the overall dia size is pretty much the same so is there really any advantage to upgrading to the 265/70/16 tire other then looks? The 245/75/16 tire usually cost less.
 
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9,088
Location
Illinois
Might see increased rolling resistance with the 265/70 size... and the ride may be different. But yes, it will look better. And you are correct in that the 245/75 will cost less.
 
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14,505
Location
Top of Virginia
Advantage? Not really. To take an example tire here, the new Bridgestone Dueler H/L Alenza Plus: The 245mm version costs $124 at Tire Rack and weighs 36 pounds. The 265mm version costs $144 at Tire Rack and weighs 40 pounds. Save your money...and the wear on your shock absorbers.
 
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40,734
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Great Lakes
Originally Posted By: RF Overlord
I thought going to a lower profile would reduce the load-carrying capability?
The profile number might be lower, but the overall sidewall height is pretty much unchanged when comparing 245/75 to 265/70. Looks like most 245/75/16 tires have a load rating of 109-111. Most 265/70/16 tires have a load rating of 111-112. The one thing the OP needs to verify is his current rim width. 265/70/16 requires a slightly wider rim.
 
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14,505
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Top of Virginia
Originally Posted By: RF Overlord
I thought going to a lower profile would reduce the load-carrying capability? Isn't that why 18-wheelers have such tall skinny tires?
It generally would if you stayed with the same width. From my understanding, load-carrying capability is all about contained air volume. If you went down in aspect ratio (a lower profile) and kept the same tire width, you'd probably see a lower load index. But a 265/70 has the same diameter as a 245/75, and is wider, so it contains more air (and receives a higher load index).
 
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14,737
Location
Central NY
I think skinny looks better , but that's just a matter of preference laugh I believe my 215/85-16 tires have a slightly higher capacity than the 245/75-16 (E- Rated) Liberator A/Ts on my father's pickup. I don't see an issue running 265/70-16 on a wheel that came with 245/70-16 from the factory. If you were go to skinnier, getting the bead to seat would be a pain.
 
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472
Location
IL
Originally Posted By: jeepman3071
The skinnier tire will also perform better in the snow. Wide tires in snow slide much easier.
How is this true? I'm honestly curious here.
 
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17,971
Location
NH
Usually one wants to compress the snow, if not into ice then into hard chunks of snow. That way the tire can find traction. That or to cut down to pavement. More weight into a more narrow area means higher contact pressure, so either one digs down to pavement or one compresses snow harder.
 
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Great Lakes
Originally Posted By: lugNutz
Originally Posted By: jeepman3071
The skinnier tire will also perform better in the snow. Wide tires in snow slide much easier.
How is this true? I'm honestly curious here.
Try cutting through a stick of cold butter with a pencil. Then try the same with a knife. Which one gets to the bottom of the plate easier? Similar concept applies to winter tires. In most cases, you want your tires to slice through the snow so that they reach the pavement underneath them easier because that's where the traction is. Narrower tire will accomplish this better than a wider one. However, if the snow is hard packed and very deep where the car just can't reach the pavement underneath, then a wider tire might offer some advantages.
 
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Washington St.
Quote:
The 245s are cheaper because it's a VERY common fleet van size
But that's usually an LT245, not the P245 the Pathfinder would use. About snow, there is less rolling resistance with the narrow tire through the snow, so that's a small gas advantage. The usual advantage is greater pressure on the snow with the narrower footprint. Taking some numbers out of the air---say the tire carries 1000# and its footprint is 4 square inches. That is a pressure of 250 pounds per square inch on the base for traction. Increase the footprint to, say, 6 sq. in., and you have reduced the pressure on the base to about 167 psi. Less grip. If the snow depth is 110% of the car's clearance, then floatation tires do a better job than skinny tires. Usually, though, the rule of thumb is the narrowest original equipment size tires for your model is the best size for snow tires.
 
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Originally Posted By: Ken2
Taking some numbers out of the air---say the tire carries 1000# and its footprint is 4 square inches. That is a pressure of 250 pounds per square inch on the base for traction. Increase the footprint to, say, 6 sq. in., and you have reduced the pressure on the base to about 167 psi. Less grip.
Based on what I've read before, the actual area of the contact patch does not change very much, but it does change. What changes the most is the shape of it. Maybe Capri can comment on that...
 
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Originally Posted By: Quattro Pete
Originally Posted By: Ken2
Taking some numbers out of the air---say the tire carries 1000# and its footprint is 4 square inches. That is a pressure of 250 pounds per square inch on the base for traction. Increase the footprint to, say, 6 sq. in., and you have reduced the pressure on the base to about 167 psi. Less grip.
Based on what I've read before, the actual area of the contact patch does not change very much, but it does change. What changes the most is the shape of it. Maybe Capri can comment on that...
First, let me state that the difference caused by tire size is small compared to the difference between makes and models of tires. Put a different way: Choosing the right tire for your conditions pays much, much more dividends than changing tire size does. The size and shape of the contact patch varies quite a bit. No, you can NOT calculate the size of the contact patch - not even an estimate. It can ONLY be determined by actual measurements. So if you have the situation described here (2 different sized tires carrying the same load), the size of the contact patch is ABOUT the same, the actual size (and shape) is governed by the make and model of tire (or more accurately, by the engineer who designed the tire). It would be a bad assumption that the size is the same, but in the big scheme of things, that assumption is sort of true. The problem is that many people think that size of the contact patch is important for handling and grip - and compared to tread compound, it is not. Oh and you've got to be very careful about the difference between a P245/75R16 and an LT245/75R16. Completely different animals - and the Nissan Pathfinder came with P type tires, not LT's.
 
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