One thing i noticed during my 1st week on the road was the gap left between the front of the trailer and the back of the unit depending on how far forward the kingpin is. For the 1st few days (and trailers) i just ignored it and got on with driving them but by Thursday it was peeing me off as i could’ve played football in the gap left by a particular trailer. The other thing i was concerned about was the weight distribution on all the axles as this trailers front sat just behind the centre of my tag axle. That night i was in woodall services and asked another driver to help me fix the problem, Which he did. After seperating the unit/trailer pulling the lever and reversing back while he watched the gap we got it much better situated. And his parting advice with a smile was “If you here a scraping noise as you jack it round just turn the radio up that’ll fix it” Gee thanks i thought nervously. So what i need to know is - Is there a recommended gap i should have and is lengthoning the gap again as easy as decreasing it was as i am now worried that the next trailer i attempt to couple upto wont reach the catch plate. Now dont get me wrong i dont want a close coupled unit I’d like ample room on the catwalk to attach suzies (and have a sly ■■■ at non smoking RDC’s lol) I just want the thing to sit/look right and be safe
You should be able to adjust it yourself before you connect up to a trailer, leave the legs down and the air lines off and pull the lever, you might even be able to slide it by hand if it is well maintained.
Just be careful when you are picking strange trailers up. Dont forget, its not just the clearance behinfd the cab to check, but the rear lights and landing leg clearance.
Dont get caught out by overloading the front axle either
If in doubt, stop faffing 
Also some trailers have dual pin positions which require a spanner to adjust them and some head and shoulders to get the grease out of your hair afterwards.
I think that was half the problem i was having, Whereas the docking plate is nicely greased the runners the fifth wheel slides back and forth on is very dry and looks like it has never been greased. So how would i move it back if i cant couple up would being sat on catwalk feet against fifth wheel and pushing with my legs do it?? As that seems like the only option i can think of. (Im a bit worried as i am running up solo to Co Durham tommorow morning to Scmitz cargobull factory to collect a brand spanking new trailer…
Reef,
The sliding fifth wheel is always adjusted by having a trailer connected, - not by brute force, sitting on the catwalk with your back against the cab !
Check trailer handbrake is on and undo all suzies, pull out the handle (always the shortest of the two ) and if possible get someone to stand at the side and watch the slider as you drive v-e-r-y slowly backwards (or forwards 
) and wait for the click. If you need a bit more, handle out again, repeat to the next click. Handle should have gone back in , so safety dog clip back into place. Into cab, try to drive forwards again once more to ensure slider does not move and is seated properly - just like the two tugs forward when you couple up. Connect lines ,trailer handbrake off , drive forward slowly and begin to turn and stop. Get out and have a good look at distances to make sure nothing is going to foul either underneath ( back lights against landing leg ) or on top ( front corner of trailer against wind deflector or anything on the catwalk , for example autolube reservoir or grabhandle etc. )
The reason the slider rails have no grease on them ( and probably rust tracks ) are that the fifth wheel has not been moved for weeks, months or maybe even years ( depending on how old the unit is ).
The fifth wheel will have been set at the ‘optimal’ position ( usually nearly or all the way towards the back of the unit,) to give the most options for the various long or short pin positions of your companies’ various trailers.
If it is a 6 wheel unit, weight distribution may not be so important. If it is a 4 wheel unit but you don’t run at maximum weight or you can supervise loading so that slightly lighter pallets are on the front headboard, again don’t worry too much about overloading the drive axle.
As Wheelnut said, if you are picking up a strange trailer for the first time, take extra care going under in case the fifth wheel has been moved further forwards and the trailer has a deep pin (quite a bit back from the front edge of the trailer ). You may go under too far and damage the front of the trailer (or even more costly the front mounted fridge motor ) 
against the back of the cab / wind deflector area.
Most trailers nowadays are tri axle 13.6m with deep pins, so if the fifth wheel is set just in front of or above the axle and looks like it hasn’t been moved for a while, I’d say leave it where it is.
***Ask the guys at the Schmitz factory tomorrow - they’re the ideal people to re-assure you and advise you about all I’ve said here !
Hope this helps,
Deesider:
The sliding fifth wheel is always adjusted by having a trailer connected, - not by brute force, sitting on the catwalk with your back against the cab !
That’s all very well until you find yourself in a yard wanting to pick up a deep pin trailer and some muppet has put your 5th wheel all the way to the front so you can’t couple it up at all. At that point you have to resort to pushing it, pulling it or hitting it with a big stick…
Paul
repton:
Deesider:
The sliding fifth wheel is always adjusted by having a trailer connected, - not by brute force, sitting on the catwalk with your back against the cab !That’s all very well until you find yourself in a yard wanting to pick up a deep pin trailer and some muppet has put your 5th wheel all the way to the front so you can’t couple it up at all. At that point you have to resort to pushing it, pulling it or hitting it with a big stick…
Paul
That is quite right Paul, but may I add. In that sort of case, use any other trailer available, just to get the slider moved and the fifth wheel right at the back. Which means of course pulling forward as far as it will go In my humble experience, the sliders never get any attention or lubrication therefore, you have a job to get it moving with the unit and I would presume, no chance of moving it by manual brute force. Then of course, you hope it locks in afterwards. I had some that were a right swine, to move and lock again. 
Deesider:
Check trailer handbrake is on and undo all suzies, pull out the handle (always the shortest of the two ) and if possible get someone to stand at the side and watch the slider as you drive v-e-r-y slowly backwards (or forwards
Unless it’s a little button in the cab.
In his original post, Reef mentioned pulling a lever, so I assumed he would be using the same unit again…
Sorry
The closer the trailer is to the cab and air deflectors (within reason), the better it is for fuel economy.
A slider should always be lubricated with oil, not grease. If it is suffering from years of accumulated corrosion, try first using diesel (a thin oil) to get it moving freely, then oil to keep it lubricated.
Deesider:
:oops:
In his original post, Reef mentioned pulling a lever, so I assumed he would be using the same unit again…Sorry
sorry, I was not saying you had it wrong. I was just thinking that if anyone else had read it & then not found the lever it could confuse them.
Deesider:
***Ask the guys at the Schmitz factory tomorrow - they’re the ideal people to re-assure you and advise you about all I’ve said here !
Hope this helps,
Alternatively ask Jost technical department (0161 763 0240). They are very helpful in regard to fifth wheel fitting positions, They can also send you drawings if you want
Thanks for all the tips… Much appreciated…
As it turned out the position i’d set it in (pretty much central between the main and tag axle) with the help of that driver at the services turned out to be perfect for the new schmitz and every other trailer ive pulled since… I just keep a very keen eye on the front corner of the trailer as im reversing onto it and if it goes past a point on my catwalk that i use as a visual reference then i know ive got to stop and fortunately that hasnt happened yet so it seems that all our pins are set the same. Like i said before im not completely close coupled but it looks right and feels right even when ive been at 44 tonnes (or very close to it) and the tag axle down… Think i might ask the fitters to oil the tracks up for me though JUST IN CASE!!! …