Thumper is a laid-back, narcoleptic, quarry machine commonly used for loosening rocks.
Thumper has been described as laid-back and just an overall cool dude. He often comes across as somewhat of a hippie, always making sure to not tread over flora or fauna. He is narcoleptic.
He initially had teething troubles and could be easily frustrated if something went wrong, although these have since been fixed.
Thumper is painted blood-red with his name painted on either side of his bonnet in white. His roof is painted black.