Hi all
Just a query more than anything but what is the process involved in extending and retracting an extendable trailer? I watched a YT vid of a guy who showed you the basics of retracting one using the red airline on another socket but not the whole process of getting it out and back in.
Anyone do this sort of work?
If the extendable is air operated, disconnect the red airline (brakes come on)
Connect the red airline to the other connection (mostimes higher or more to the outside of the trailer)
Some trailers are operated with a button, similair to a shunt button, these buttons are placed on the front part of the extendable.
Anyway the airline or the button will operate the locks.
You could check if the locks are retracted, but I tend to shunt careful a little forwards and backwards.
If the locks are free, extend the trailer to the required length.
Activate the locks (they look like a spring brake chamber with a flat pin on the end) with either disconnecting the red line from its connection, or operate the button.
Leave the brakes on, don’t connect your airline yet.
Shunt careful forward and backwards until the locks engage on both sides.
Check (use a torch if needed) if all the locks are engaged, connect your airline to its normal connection and ready to go.
There are probably the odd one which is old fashioned with manual pins, be very careful with these, as I pulled one to far and the end stop was missing, ending up with two trailer halfs.
It’s easy once you have done it once or twice, but never get complacent en forget to check the locks
Thanks for that mate. I haven’t come across one yet, but sometimes I see something and just want to know how it works out of curiousity 
I used them a couple of times but it was easier just too Bung a marker on and a beacon