a bit of info on something that scared me nearly to death last week. My truck had been handling everso very slightly differently and getting progressively worse over the week. Got it checked out, tyres, steering, air bags the lot, workshop and dealers couldnt trace fault, it came to a head when pulling onto A12 out of Chelmsford fully freighted, on slip road with a fair lick on indicating to get onto nearside lane and the truck just kept on a straight line, drifted across both lanes heading toward central reservation. Tried to pull the old girl back but the heavy braking seemed to make matters worse, I managed to salvage the situation and got into a layby sharpish. After serious going over it was found that the fifth wheel was bone dry and shiny. On our fleet we keep to one trailer never dropping it relying on the fifth wheel getting grease at service and inspection and this hadnt been done on its last service a few weeks earlier so with a good load on and under heavy braking no way was this truck going to bend with that sort of weight on an ungreased fifth wheel. Moral of the story? dont be complacent like me, if you stick to one trailer never dropping it make time to just to check, I didnt and it appeared neither did the workshop
sorry, but from what you have said, it would not have been greased for a long time, not just missed at last service/inspection, it would have been missed at many 
It is an important lesson.
I can normally tell when I have a dry plate with the tail wagging the dog, it is worth checking and in the past there was normally an open tub of grease with a stick in it next to the oil tank in the garage.
It kept the apprentice on his toes too 
Looks like you need to drop it once a week if nothing else to check the jaws are working and in place too
Wasn’t there a “dry” 5th wheel system developed a while ago which used a hard plastic/silicone type sleeve? Never seen one and suspect it was incompatable with using multiple trailers some with dry and others with conventional greased 5th wheels.
You need a 5th wheel with neoprene inserts, or a lube liner as an after market fit.
Used to use these and couple the jaws upto the autolube, remember those; VBG made a 5th wheel with a gease ■■■■■■ in the jaws. We only dropped the trailers when we got a new unit. They were washed coupled, serviced coupled, went for test coupled, everything, and you never got the tail wagging the dog. Bear in mind we used to change units fairly regularly, every two or three years. I have to admit that whilst it all worked fine as regards running, the problem occurred when you can to uncouple after two years, pulling the handle could take longer than expected.
Something I want to know is why it isnt checked atleast once a week■■?
I always check mine on the monday, or friday when I drop my trailer to go give my unit a wash. Surely this is another thing that should be part of a routine check by the driver■■? I dont mean to sound snippy or to attack Mike as he obviously did a good job to avoid a major incident. I’d have severe words with the workshop or mobile mechs that service/inspect the unit, because obviously they aren’t doing anywhere near properly. The guys that do ours, Three Counties Vehicle Hire, now have to have a driver in the yard to drop the trailers when they inspect the units EVERY 6 weeks.
I check my fifth wheel every week and slap a bit of grease on there if necessary. If I have the same trailer for a couple of weeks I’ll drop it at the end of the week and check it while i fuel up. Not only is the fifth wheel the major component stopping the trailer unhitching and trying to overtake you, but they are flippin expensive to replace.
we had a similar thing hapen once…unit was steam cleaned and went for mot…came back and was put under a tanker and off down the road before we greased the 5th wheel up!!
25 miles down the road and the driver called in with a problem…same symptoms…
Blimey, what’s it like to never have to change trailers?
On saturday last, if all had gone to plan (It didn’t… last collection place closed) I would have had 6 trailers on.
Thanks for the heads-up, Mike. That’s not a scenario I would have thought of
(and due to my inexperience, I worry about nearly anything that could / might / should happen! I’ll add this to my “potential nightmare” list! 
)
It sounds like you did well to avert disaster. 