I have a prime mover with a 50mm tow pin, can it legally tow a draw bar with a 57mm towing eye.
I hope someone could advise me
Thanks
Paul
Hi Paul i would ask Euro Axles stoke or SV Tech at Leyland i think they deal with these type of things often.regards Dan
I don’t know the legal answer but it sounds to me like the type of thing that would end in tears before bedtime unless you shimmed it out in some way.
Spoke to guy at VOSA a few months and said it would be ok as long there is less than three quarter play in the towing eye.
Still not convinced though. I have searched the Internet high and low without success.
from your username, i would presume that you are a driver training company?
think about this from the learners viewpoint…
you are leaning to drive C+E and using a bodged up combination that rattles and bangs about every time you did a manoeuvre, and would not reverse where you expected it to go…
would you use this company, or go to another one?
Shuttle spanner quite agree with you. I am only looking to use it as a reserve training combination in the event my first choice prime mover was to be off the road.
I think he has answered your question (as did I), regardless of the legal position you need to make sure that the pin and eye are compatible.
elmet training:
Shuttle spanner quite agree with you. I am only looking to use it as a reserve training combination in the event my first choice prime mover was to be off the road.I take it you can’t answer my question then!
it is shuttlespanker, not shuttle spanner 
and, sorry, no, i can’t answer the legality of what you are proposing
i was merely pointing out the possible ‘issues’ you might have with trainees, please don’t think i was having a go at you or your methods, whatever you decide to do, i hope it works well for you 
My brother runs two draw bar couplings he thinks they have to match all his are 57mm.
The HGV inspection manual gives the following as a reason for failure
“has excessive movement between the vehicle and trailer”
I’m pretty sure a 50mm pin in a 57mm hole would count as excessive movement 
dft.gov.uk/vosa/repository/2 … Manual.pdf
.
It wont fit anyway as the 57mm eye has a broader rim that wont got far enough into the 50mm coupling to allow it to drop. You can get bolted eyes that are interchangable, so you could swap over if needed.
Cold Up North:
It wont fit anyway as the 57mm eye has a broader rim that wont got far enough into the 50mm coupling to allow it to drop.
Forgot that 
You can get bolted eyes that are interchangable, so you could swap over if needed.
That’s probably your best option
Thanks everyone. I am going to get a new 57mm jaw fitted.
Is yours bolt on or welded on?
Not cheap £700+vat. That’s for the Rockinger bolt on make. But the sensible things to do.
Another option could be to swap the coupling rather that the eye.?
On 3.5t type plant trailers with ring couplings there’s often quite a lot of slop on the pin depending on the hitch on the tow vehicle. Nato type couplings also often have quite a lot of slop so although not ideal I’m not sure it’s illegal. Also on test, they rarely do a lot of investigation on couplings particularly if it’s not booked in combination either. I’ve take trailers to test with elderly yard shunters in urgent need of a fifth wheel jaw kit and nothing’s ever been said and obviously won’t have been when the unit went to test itself.
Harry Monk:
I don’t know the legal answer but it sounds to me like the type of thing that would end in tears before bedtime unless you shimmed it out in some way.
And now for something completely different…
I agree 100% with Harry 
Then the shims wear away and the slop returns.
Reminds me of an old ifor williams with the imperial sized ballhitch that decided to undo during breaking and shunt my car up its arse when coming to a stop because my ball hitch was a different size to the hitch.