Question about Cena & R-Truth?

A few years back, there was a story about R-Truth and John Cena being in an altercation at an airport while Truth was still with TNA. Around the same time, Truth went on YouTube and had some harsh words for Cena in a rap song. They’ve claimed to be friends since Truth returned to WWE or at least did some backstage stuff during the Cena/Nexus storyline on Raw. Was there ever any real heat between the two? anyone know??