Silber (Folksinger's Wordbook page 27) isn't much different:

MY SWEETHEART'S THE MULE IN THE MINES

My sweetheart's the mule in the mines.
I drive her without any lines.
On the bumper I sit
And I chew and I spit
All over my sweetheart's behind.

Well, that covers all the versions cited by the Traditional Ballad Index except for I Hear America Singing! Great Folk Songs from the Revolution to Rock (Hazel Arnett, 1975), which I don't have or don't find.

A couple of YouTube videos wouldn't hurt, would they

Here's Joe Glazer: https://www.youtube.com/watch?v=pyNbVjMJink

And Pete Seeger: https://www.youtube.com/watch?v=g2glwmGpbFc

Malvina Reynolds started her "You Can't Make a Turtle Come Out" with the same melody, expanded.