Musnad Ahmad 770:50

Sufyan narrated to us, al-A’mash narrated to us, from Ibrahim, from Hammam, who said: I saw Jarir ibn Abdullah performing ablution from a leather container, and he wiped over his leather socks. They said: "Do you wipe over your leather socks?" He said: "I saw the Messenger of Allah, may Allah bless him and grant him peace," and he said once: "wiping over his leather socks." This hadith used to amaze the companions of Abdullah, and they would say: "His conversion to Islam was only after the revelation of [Surah] al-Ma'idah."