Should I grease my tow-ball is asked by caravan owners worldwide. A recent poll in Australia’s Caravaners Forum.com showed that slightly over half do so, but primarily to reduce wear.
That seemingly overlooked by almost all respondents on that forum is that tow-ball friction plays a vital role in reducing caravan sway. Those owners who grease them unwittingly prejudice safety for the possible need to renew the tow-ball every ten or so years. In practice, however, a non-greased tow-ball has negligible wear. Even it were to need replacing, the cost to do so is a mere A$15-25.
So do NOT grease that tow-ball – nor use any liquid or powder that may reduce that vitally needed friction.
Adding tow-ball friction
The world-wide AL-KO company produce a tow-ball that has four friction linings forced against the tow ball from both sides plus the front and rear. In technical terms, they exert the equivalent clamping torque of 320 Newton/metres (236 foot-pound) force. In Australian terms, this is ‘b-y tight!’. Swaying or pitching movements are effectively suppressed before they become serious.