Nursing to sleep 😕

HELP- I am trying to get my little one to stop nursing to sleep. He falls asleep so quickly and easily which makes it so easy to continue. Lately, however, he pretty much only falls asleep this way. We just went on two 11 hour road trips and only napped when I contorted myself and stuck my boob in his mouth. He hates pacifiers and bottles. Any tips to change this behavior?