Hi ive just had a tow bar fitted to my mondeo the fitter tells me to have the bolts that hold the ball on need changing every year as they tend to stretch, ive been caravanning some 20 years now and never heard of this has anyone else . Tom
Mick you're right what you say but it's not uncommon for bolts to shear I've sheared quite a few 16mm bolts but it's mainly been taking old bolts out of machines using the scaff tube method (not recommended).Yes, over torquing a bolt can distort it slightly, but not to the point of failure as you say, especially given the diameter of a towball attachment bolt. I don't think that a person would stand much chance of shearing one of those. Most of the time over torquing will result in stripped threads, which of course is just as dangerous.
"I don't think that a person would stand much chance of shearing one of those"Yes, over torquing a bolt can distort it slightly, but not to the point of failure as you say, especially given the diameter of a towball attachment bolt. I don't think that a person would stand much chance of shearing one of those. Most of the time over torquing will result in stripped threads, which of course is just as dangerous.