I wish the major tire retailers, or the manufacturer's web pages, would provide (publish) the ply information that is shown on their tire sidewalls.
I know that sometimes Tirerack list some information about the internal tire construction but it isn't consistent and often incomplete.
I was looking at physical examples from Goodyear, Toyo, Kumho, Douglas, GT Radial. All were "S" rated tires except the GT Radial which was "T" rated. All of them showed:
Tread: 1 Polyester + 2 Steel
Sidewall: 1 Polyester
Of course, this basic construction seems pretty common in the everyday class of all-season "S" rated tire.
What I found of interest is the description on the sidewall of the 215/70/15 Starfire 340 ("T" rated) tires on my van. It shows
Tread: 1 ply Polyester + 2 ply Steel, 1 ply nylon
Sidewall: 2 ply Polyester
I wonder how or why they end up with 2 plies of polyester on the sidewalls but apparently 1 of these plies does not continue on around the casing in the tread area?
It would seem that any trade off in the slight amount of material savings would be offset by a more complicated design and manufacturing process to not extend that 2nd ply completely around the tire as they do the first?
From what I read, that 2nd ply does make for a stronger sidewall but I guess there is a trade-off which might include slight added cost, a weight penalty (fuel economy) and slightly stiffer or harsher ride. Any other ideas?
I know that sometimes Tirerack list some information about the internal tire construction but it isn't consistent and often incomplete.
I was looking at physical examples from Goodyear, Toyo, Kumho, Douglas, GT Radial. All were "S" rated tires except the GT Radial which was "T" rated. All of them showed:
Tread: 1 Polyester + 2 Steel
Sidewall: 1 Polyester
Of course, this basic construction seems pretty common in the everyday class of all-season "S" rated tire.
What I found of interest is the description on the sidewall of the 215/70/15 Starfire 340 ("T" rated) tires on my van. It shows
Tread: 1 ply Polyester + 2 ply Steel, 1 ply nylon
Sidewall: 2 ply Polyester
I wonder how or why they end up with 2 plies of polyester on the sidewalls but apparently 1 of these plies does not continue on around the casing in the tread area?
It would seem that any trade off in the slight amount of material savings would be offset by a more complicated design and manufacturing process to not extend that 2nd ply completely around the tire as they do the first?
From what I read, that 2nd ply does make for a stronger sidewall but I guess there is a trade-off which might include slight added cost, a weight penalty (fuel economy) and slightly stiffer or harsher ride. Any other ideas?