From the formation of the Interstate Highway System, the highway was gradually upgraded to Interstate Highway standards and signed as I-80.
fɹʌmðə fɔːɹmˈeɪʃən ʌvðɪ ˌɪntɚstˈeɪt hˈaɪweɪ sˈɪstəm, ðə hˈaɪweɪ wʌz ɡɹˈædʒuːəli ʌpɡɹˈeɪdᵻd tʊ ˌɪntɚstˈeɪt hˈaɪweɪ stˈændɚdz ænd sˈaɪnd æz aɪ ˈeɪɾi.