ɪn nˈaɪntiːnhˈʌndɹɪd fˈoːɹɾi θɹˈiː, ˌɛsˈeɪtʃ ˈeɪɾi fˈoːɹ wʌz ɛkstˈɛndᵻd nˈɔːɹθ; ðə hˈaɪweɪ nˈaʊ kənˈɛktᵻd tʊ ˌɛsˈeɪtʃ nˈaɪn, fˈɔːɹmɪŋ ɐ θɹuː ɹˈaʊt fɹʌm jˌuːˈɛs sˈɛvənti fˈaɪv slˈæʃ tˈuːhˈʌndɹɪd sˈɛvənti tʊ ˌɛsˈeɪtʃ nˈaɪn.
In 1943, SH-84 was extended north; the highway now connected to SH-9, forming a through route from US-75/270 to SH-9.