The latest issue of the Journal of Biblical Literature contains Michel Gourgues’s article, “Jesus’s Testimony before Pilate in 1 Timothy 6:13” (JBL 135:3 : 639-48)- the abstract can be viewed here. Gourgues notes the fact that outside of the Gospels and Acts, 1 Timothy is the only other place Pilate is mentioned. Arguing from the context and structure of the passage in 1 Timothy 6 and verbal parallels with the account of Jesus’s trial in John, Gourgues argues that 1 Timothy 6:13 draws from John’s gospel (or traditions behind John’s gospel). He sees this as confirming a later date for the composition of 1 Timothy.
I appreciated Gourgues’s attention to the context and structure of 1 Timothy 6. He mentions but dismisses (rightly, I think) those who explain this text as simply pre-formed material inserted into the letter. He notes that the pieces fit together reasonably so that if pre-formed material is used it has been shaped to fit the context.