I am planning to replace my worn Dunlops with Michelin Defender LTX M/S, and have gone back and forth on size between 285/60R18 and 275/65r18. I will not be buying the LT version of any tire, as it isn't needed for my uses. On the Tire Rack website, I notice Tread width is wider for P rated tires versus XL or LT rated tires of the same section width. Examples:
P275/65r18 sec width 11" tread width 9"
LT275/65r18 sec width 11" tread width 8.6"
Each Defender tire size for which there is a P and an LT version has a more narrow tread width on the LT version, by 2 to 4 tenths of an inch.
285/60r18XL sec width 11.5" tread width 8.9"....a narrower tread on the 11.5" tire versus the 11" 275 width tire.
Questions:
1.) why would tread be more narrow on heavier load tires?
2.) For on road use, wouldn't the tread width be the important measurement, versus section width? (I understand the higher load capacity and tougher construction of the heavier load tires, I'm asking about on road performance like braking, cornering, etc.)
3.) Is there any on road performance advantage (beyond load carrying) of the 285/60r18XL with a 8.9" tread, versus the 275/65r18 with a 9" tread?
4.) The stock Dunlops are listed as 11.5" sec width, 8.6" tread width. The 275/65r18 Defenders have a wider tread (9") in spite of a 0.5" narrower section width. This surprised me. Any thoughts?
Thanks for your perspectives.
P275/65r18 sec width 11" tread width 9"
LT275/65r18 sec width 11" tread width 8.6"
Each Defender tire size for which there is a P and an LT version has a more narrow tread width on the LT version, by 2 to 4 tenths of an inch.
285/60r18XL sec width 11.5" tread width 8.9"....a narrower tread on the 11.5" tire versus the 11" 275 width tire.
Questions:
1.) why would tread be more narrow on heavier load tires?
2.) For on road use, wouldn't the tread width be the important measurement, versus section width? (I understand the higher load capacity and tougher construction of the heavier load tires, I'm asking about on road performance like braking, cornering, etc.)
3.) Is there any on road performance advantage (beyond load carrying) of the 285/60r18XL with a 8.9" tread, versus the 275/65r18 with a 9" tread?
4.) The stock Dunlops are listed as 11.5" sec width, 8.6" tread width. The 275/65r18 Defenders have a wider tread (9") in spite of a 0.5" narrower section width. This surprised me. Any thoughts?
Thanks for your perspectives.
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