A short sexual encounter where the man unclips the woman's bra and runs his index finger down the middle of her back, the "road", and then proceeds to go to sleep. There is also the possibility of causing a "traffic jam" where the man proceeds to finger the woman for a short moment. After this is done, the woman is often passed over to "the bro", much as a road trip would continue by taking turns driving.
"Ayo bro I'm bout to road trip this shawty"
"Aii bet, lemme know when it's my turn to step on the gas"