Related על סוכה 2:3

One who puts a [schach] covering over a wagon that is higher than 10: Rabbi Yosi b. Rabbi Yehudah says in the name of Rabbi Yosi, One who sleeps under [that] wagon is like one who sleeps under the bed.

If one puts a canopy of leaves over a chariot ten handbreadths high, R. Jose son of R. Yehuda says on behalf of R. Jose: If one who sleeps under the wagon, it is as if he were sleeping under the bed.