Tow Bar Tech Question

Spanielzrus
Spanielzrus Forum Participant Posts: 3
edited April 2014 in Towcars & Towing #1

Hi folks, first post to forum so appologies if I'm in the wrong place.

Just fitted a brand new b'rand name' detachable towbar to our Freelander 2.   Before I go any further can I say that when the bar was fitted all the bolts and fixings were tightened as specified with a torque wrench and checked 'belt and braces' by a qualified
individual with a second torque wrench.

All went well, until after about 1/2 hour of towing, I noticed that the towball had 'sunk' by about a good 1"-1.5" causing the van to sit sit more 'nose down' than when first hitched.  Although towable the jockey
wheel was much closer to the road so took it easy until we were safely home.

Having investigated I discovored that the four bolts that retain the towbar housing, although still tightened to torque, had moved, allowing the bar to drop until the bolts stopped on the tow bar mounts.  This small movement is obviously magnified at the
towball end.

Does anybody out there know if i could replace the M12 8.8 retaining bolts with higher tensile10.9 bolts which can be torqued tighter?  Would this stop the movement or might the extra torque damage the housing?

Needless to say the manufacturers have not been much help so far.  I'm still on the case but would appreciate any (constructive) replies.

Thanks again.