Yes, it was a big hit for them back in the day, maybe their only hit? Used to hear it on the radio all the time in the 70s.

It made the #8 spot in the Rolling Stone 15 greatest Stoner Songs of all time list : https://www.rollingstone.com/music/lists/the-15-greatest-stoner-songs-20110420/brewer-shipley-one-toke-over-the-line-19691231