Been a while but had the same issue with a previous employer. If memory serves there is a stepped spring on one end of the mirror arms that can have the holding tension increased by tightening the nut below it. It was a workshop job at the time not least because the company didn’t allow drivers to meddle with vehicle maintenance.
Are the trucks brand new? If so it doesn’t reflect well on the dealers pre delivery inspection does it.
Maybe poster Norb can advise have you tried a pm to him?
If no one’s bothered about getting this fixed, i’d be inclined to get some really brightly coloured tape and attach two tensioned lines from the mirrors to the front corners of the cab, maybe even link the mirrors with the tape threaded through the grill (wedding car style) for added effect, it’ll look bloody silly and eventually someone responsible and high enough in the pecking order will start asking wtf is going on.
embarrass them into action…oh and don’t forget to fill in a fresh defect note every day until fixed.
I drive a Daf cf with the mirror guards for a builders merchant.
Exact same problem.
You can tighten the nut at the top of the arm and that helps a bit.
Thankfully it’s only the drivers side that seems to be affected especially in a head wind.
Duncan
Perhaps keeping the speed down to about 45 mph will be enough to sufficiently reduce the force acting on the mirror and save a couple of percent fuel also? When questioned about the amount of time deliveries are taking could be a good time to remind them about the mirror arm defect!!
In the mean time it will mean more pay for lees work and may even help perpetuate the myth that there is a driver shortage…