Jackson, TN
Traveling through this area we have 147.210 PL 107.2 located in Jackson, TN. It gives fairly good coverage from about Exit 101 to around Exit 56 along I-40.
There is also a repeater 146.685 (no tone) in Lobelville @ exit 143. I haven't used it quite awhile so I can't say for sure its up, but if it is, it gives good coverage just west of Nashville, down to about Exit 116 along I-40. Even though it has a large footprint, its not that active, so you may have to throw your call out a few times to get a response.
What dates are you heading this way?
Hope this helps,
Richard
KB4YTM