OEM tires weight question

Need to replace my 265/60 R18 Michelin LTX MS2. Comparing the "best" alternatives to this tire on-line, there really are only 3 options for my use of the truck. One of the brands out there, Goodyear, rates their Assurance tire weight at 31 LBS., while Michelin and Bridgestone Dueler LX weigh in at 39 LBS. Same size tire. How does the same size tire from one manufacturer weigh so much less than it's direct competitors?
32 LBS of unsprung weight savings. Interesting.

 

I would venture to say that different manufactures use different material, compounds, belts, etc. when manufacturing a tire. Some also have more tread, are rated higher for weight, etc......so it makes sense in my mind that manufacturers do things a bit differently equating in different weights for the same size tire.

 

I run duratracs. And one reason is because there one of the lighter tires out there.but…. They have a weaker side wall. In my opinion there a great tire in the snow they look good but there getting noisy getting close to 40k miles on them but plenty of life left