Sunfan wrote:
What do you think about taking I-20? Thinking maybe we could visit White Sands NP again (weather should be fine) and then head East on I-20 through Dallas (or possibly drop down to I-10 and visit family in San Antonio, Houston).
Since you asked about I-20 I will comment about that portion of your contemplated route. From Dallas to Nashville is about 665 miles. One good thing: from west to east I-20 is an easy route south around Dallas/Fort Worth on the south. I have towed my fifth-wheel on this route several times and have never had to slow down.
April is a beautiful time in East Texas as the wildflowers are blooming and the temperature/humidity hasn't reached Summer's awful highs. There is a super fine state park at Tyler just off I-20, but the park is popular and would require advance registration.
The direct route to Nashville from Dallas is to take I-30 to Little Rock and I-40 on to Memphis and Nashville. (the interchange from I-20 to I-30 would be on the east side and still avoid much of the city traffic.)
You have mentioned the alternative to drop south. If so, you would stay on I-10 and not take I-20. In April this would take you to the Texas Hill Country and such towns as Kerrville and Fredericksburg as well as to San Antonio. It would be a great time for a visit to Fredericksburg, a quaint town with German heritage. The bluebonnets would likely be near their peak. To really enjoy this area would require staying over for a day or two at least.
You may take an entirely different route, I am commenting only on the portion of I-30, I-30, and I-10 within Texas. I know these routes well as I live just 20 miles north of I-20 not far from the Louisiana state line. Let me know if I can help.