My memory is hazy on this now since it was 20 years ago. At the time I used to service car transporters belonging to Axial. The vast majority were Lohr MAN F90 4x2 chassis which were either 50/50 split deck length or a slightly longer trailer. There were at least two styles of trailer either 16" twin wheel or 20" single wheel axles. Whether these were tandems or tri axles I just forget. IIRC there were one or two of the larger 40/60 split.
At the time we were told that the company had grave concerns about the security of the coupling devices, having lost trailers on more than one occasion. We were all given training by a company engineer on the specific requirements of transporters in general and Lohr in particular. Apart from the split worm nut on the columns there was great emphasis on checking the couplings and the attachment and condition of the rearmost (towing cross) member. At least one of the lost trailer incidents had involved the rear cross member being ripped out of the vehicle. ISTR having to change all the securing bolts as part of the maintenance programme.
There were a variety of couplings in use and since this was my last involvement with drawbar trailers on a regular basis I may be confusing manufacturers. There were VBG and Ringfeder manual and automatic standard pattern set ups and a one I had never seen before or to my knowledge since. This has a sphere about half the size of a football on the front of the trailer and two sprung-loaded claws attached to the back of the unit. The claws were then held together with several large bolts ( which had to be cleaned and examined). Because the yard was crowded, trailers were frequently left uncoupled. Being on night shift, hitching up to these ball type couplings was an absolute nightmare, not only because seeing was difficult and the jaws just wouldn’t clamp shut, but to fit the bolts you had to work almost lying under the back of the vehicle. It seemed that the normal situation would be to find the trailer parked in about a three inch deep puddle.
Are these abominations still in use or have they now been done away with, and if so why? Am I right in thinking that some of the 40/60s use a mini fifth wheel coupling these days?
Cav, car transporter drivers almost never get involved in (dis)connecting their charges, companies prefer the mechanics to do the job…something i for one was very grateful for due to the state things get in down there…so the makes and types though i’ve seen three different sorts i can’t comment on.
I did have an ex Axial FL12 with the Lohr ‘cake stand’ tandem twin 16" wheel trailer up till 2005, that was a really involved job to disconnect, probably the claw jobbie you mention, it was a huge ball type of coupling, which again never gave any cause for concern and didn’t seem to wear, very sad to have that motor replaced.
I have seen one Irish motor that the entire rear crossmember had ripped out by the roots dropping the loaded trailer where it sat on the A14 at an off ramp roundabout.
One comment i will make is that some drivers don’t realise how little angle you can put when turning one of these before the hitch reaches its limit, and i’ve seen all sorts of damage including bent trailer chassis when the driver has tried to jack-knife the vehicle artic style, so i wonder if the ripped out and other causes of lost trailers is often due to drivers exerting regular too tight manoeuvers? i presume when you steam clean the area and have a good look you can probably see the damage where contact has been made, you can certainly see the bent chassis…
I’ve never personally had any problems like this, and considering the shambles and bodgit and scarper maintenance that was the norm on the scabby mob i started on the cars with (ex Toleman near enough scrap motors mainly, but some MTL bodies too which had a weird and wonderful unique hitch which had most mechanics scratching their heads) all those years ago, it bears testament to just how good the hitches were and are…especially when you consider the soaking with all manner of road filth they are bathed in continually this time of year.
I drive car transporter you can’t jack knife or turn tight you will damage the couple and damage cars trust me I’ve done it deck 7 behind cab will hit deck 8 on the front of trailer and if loaded you will cause damage, plus we never swap trailers as they are built as a matching pair
look at outlander on deck 5