I used to think that the Huey Lewis and the News song "I Want a New Drug" went "I Want a New Truck".
A childhood belief about misheard lyrics

others believed things like this
- Huey Lewis's "Hip to be square" - in 3rd grade I could have SWORN it was "hit the beef square". ????Anon
- When I was little I used to believe that comedian Jerry Lewis and rocker Jerry Lee Lewis were the same person.— Paul
- I wanted to grow up and be a truck. Not a truck driver, a truck. Anon
- I used to believe that Sheri Lewis from the show Lambchop was my Auntie Rose. the look so much a like!— Nirveli
- for some time I used to think that at a drug store people really sold drugs.— NEO_ryu
- I used to believe that drug stores sold illegal drugs and I couldn't work out how they got away with it.— Bigg Jase