OCD Overland
Explorer
This is probably a dumb question, but why do manufacturers offer conventional LT tire sizes that are only slightly off from their LT-metric counterparts?
For example, if I want 35" BFG All-Terrain KO2's for a 17" rim, they offer both an LT315/70/R17/E 121 S and also an LT35x12.5R17/E 121 R.
The obvious difference between the two is the speed rating, R vs S, but they're also sized ever so slightly differently (a tenth of an inch here or there) and the conventional tire is also a bit heavier. But both are LT's, the load rating is the same, there's nothing to indicate any construction or tread difference, and they cost roughly the same.
These two tires must be different for a reason, but I have no idea why. I can only see that the conventionally sized tires in general have the lower speed rating and seem to be slightly heavier.
So is there some general rule that I don't know about for the difference between tires that are sized conventionally vs metric? Why would I choose one over the other? I can only assume that it has something to do with the sidewall construction, but I can't find anything that would indicate if that's so or what the difference would be. I just feel like this must be some basic bit of car info that everyone must know but me, because I can't find it explained anywhere.
For example, if I want 35" BFG All-Terrain KO2's for a 17" rim, they offer both an LT315/70/R17/E 121 S and also an LT35x12.5R17/E 121 R.
The obvious difference between the two is the speed rating, R vs S, but they're also sized ever so slightly differently (a tenth of an inch here or there) and the conventional tire is also a bit heavier. But both are LT's, the load rating is the same, there's nothing to indicate any construction or tread difference, and they cost roughly the same.
These two tires must be different for a reason, but I have no idea why. I can only see that the conventionally sized tires in general have the lower speed rating and seem to be slightly heavier.
So is there some general rule that I don't know about for the difference between tires that are sized conventionally vs metric? Why would I choose one over the other? I can only assume that it has something to do with the sidewall construction, but I can't find anything that would indicate if that's so or what the difference would be. I just feel like this must be some basic bit of car info that everyone must know but me, because I can't find it explained anywhere.
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