Just wondering about this as I had to make a delivery today where one of the airlines was shorter than the others which made me have to make a couple of shunts to keep the cab angle lower than I’d have liked.
Yes… they have to reach the trailer!
If they are slightly short, or you have to manoeuvre to a very sharp angle, take them off, press the shunt button, do your tyre crunching turn, and put them back on.
Saves stretching them, and avoid them to get covered in grease, and stops them from getting ripped offf 
Cheers mate, just wondered. Did my checks and noticed this one suse reached but a lot less give in it than the others so kept that in mind. Went to back up to a bay and space was tight in front so rather than mess about with taking them off and using the shunt valve, I reversed as far as I could and then drove forward to take some of the angle off it and backed it up ok.
Had a bloke shaking his head and smiling when I got out the cab and he said something like ‘you could’ve got an oil tanker in there in one go’. tbh, I’m too old and long in the tooth for people who think they know it all and were born experts but did mention I had a short airline and rather than messing about taking them off and using the shunt valve it was easier and quicker to take a shunt. His answer was ‘excuses, excuses’.
Theres no specific lenghth just long enough for at least 75degree turn taking into account how close coupled it is. I pull long pins with a 4x2 and trailer to cab is very close so have the lines as short as possible…
There is an easy way to check for the correct length.
A standard length airline should be capable of knocking an agency mans glasses off from a range of 4 feet when used like a catapult.
Grab the nearest limper and try it out. ( I always get one to stand 3 feet away when I try it ).
eagerbeaver:
There is an easy way to check for the correct length.A standard length airline should be capable of knocking an agency mans glasses off from a range of 4 feet when used like a catapult.
Grab the nearest limper and try it out. ( I always get one to stand 3 feet away when I try it ).
PMSL… 
andy_s:
Had a bloke shaking his head and smiling when I got out the cab and he said something like ‘you could’ve got an oil tanker in there in one go’. tbh, I’m too old and long in the tooth for people who think they know it all and were born experts but did mention I had a short airline and rather than messing about taking them off and using the shunt valve it was easier and quicker to take a shunt. His answer was ‘excuses, excuses’.
Try one of these next time…
If I wanted to listen to an ■■■■■■■,I’d ■■■■.
I can’t believe that out of 10,000 sperm, you were the quickest.
Hey, your village called,they want their idiot back !
Remember when I asked for your opinion ■■ Me neither!
Newer style lines (my electric lines) are closer /tighter coiled but they do stretch as good as the others 
eagerbeaver:
There is an easy way to check for the correct length.A standard length airline should be capable of knocking an agency mans glasses off from a range of 4 feet when used like a catapult.
Grab the nearest limper and try it out. ( I always get one to stand 3 feet away when I try it ).
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+1 …yep…that’s the post of the year sofar for me… 
caledoniandream:
Yes… they have to reach the trailer!If they are slightly short, or you have to manoeuvre to a very sharp angle, take them off, press the shunt button, do your tyre crunching turn, and put them back on.
Saves stretching them, and avoid them to get covered in grease, and stops them from getting ripped offf
Can’t always do that as 99.9 % of our trailers and a fair few other company’s have that feature locked out .
I can confirm that if you forget to take them off when uncoupling, then you can get almost a tractor unit’s length from the trailer before you have to make the embarrassing phone call. 
No legal length but they must not touch or rub against any object between the truck and trailer, they must have no chaffing or rub marks anywhere along the lines. I always used rubber bungees to keep to keep them off the catwalk when I lived in the UK.
Harry Monk:
I can confirm that if you forget to take them off when uncoupling, then you can get almost a tractor unit’s length from the trailer before you have to make the embarrassing phone call.
I have noticed newer ones being almost a trailers length Harry! 
eagerbeaver:
There is an easy way to check for the correct length.A standard length airline should be capable of knocking an agency mans glasses off from a range of 4 feet when used like a catapult.
Grab the nearest limper and try it out. ( I always get one to stand 3 feet away when I try it ).
Should try it at 2 feet its more fun when it wrapped round there head.
Harry Monk:
I can confirm that if you forget to take them off when uncoupling, then you can get almost a tractor unit’s length from the trailer before you have to make the embarrassing phone call.
iirc there’s an image on here of a unit coned off, which had pulled away from a dropped trailer without uncoupling the suzies, stretching the suzies 1-2 truck lengths
Hijacking a thread here. Say you have a slightly stretched susie. I’ve heard if you cable tie it up tight and pour boiling water over it then it will shrink back to size. True or drivers pish talk?
I’ve currently got about 3/4 coils of the line cable ■■■■■■■ to stop it catching grease.
Susies can range from 4ft 9-6ft odd… [FACE WITH TEARS OF JOY]
Sent from my SM-G900F using Tapatalk
merc0447:
Hijacking a thread here. Say you have a slightly stretched susie. I’ve heard if you cable tie it up tight and pour boiling water over it then it will shrink back to size. True or drivers pish talk?I’ve currently got about 3/4 coils of the line cable ■■■■■■■ to stop it catching grease.
Never poured boiling water on them but have immersed them in a drum of boiling water to get them back to shape.
Mine are a bit stretched but not heard about this hot water trick. Does it work. I’m very close to having to bungee up but I hate the look of it.
Did anyone remember seeing a clever new idea for the Susies that some company invented
years ago… if I remember, the electrical and air lines were repositioned nearer to the front
of the fifth wheel, rather than the usual back of the cab position
This meant they didn’t get stretched at all, as they pivoted with the trailer on a kind of
sliding mechanism.
Perhaps the idea flopped as I only remember seeing them on a few trucks years ago
( Possibly Christian Salvesen ) then I never saw them again.
I tried to find an image of this innovative design but I couldn’t find any 