valhalla360 wrote:
The ABCD... is an old system based on how many nylon plies the tire is made from...
I'd have to go back and look to verify, but I don't think that the OEM 245/75R16 tires off Dad's 1989 Chevy C2500 Scottsdale have an LT designation or an ABCDE load range rating. They just say "10 ply rating."
So ply rating was how it started. Then at some point in the 80's or 90's they must have adopted the LT-ABCDE system. Later on they started this load index/speed rating deal. Now pickup truck tires have ALL THREE which makes it confusing. IF you're not up on the legacy nomenclature you and the customer are talking two different languages.
