never touched it before as never needed too , but today had to drag 23 pallets of very heavy tomatoes down the trailer and after 10 was knackered ,had already dropped the unit suspension so had ago at trailer ,easy enough [ leaver straight down, lift to the right suspension raises, to the left lowers , but how do you re-level it , i did it by pulling lever to the left so dropping it down to what looked about level , but how do you know for sure its level ,must be better way than by eye or is that it,
also when you run with the lift axle up [ note ive only ever had 4x2 before] it looks like the back of the units up in the air to what it is with axle down ,does that affect the height of the trailer or is it a bit of a optical illusion . ta
you reset it by putting it back at the centre automactically does it for you
Centre the trailer adjustment lever and the trailer will return to its “running height”
If the unit is a twin steer/lift when you lift the axle it raises the rear axle a bit so as to increase clearance between the centre axle, its associted components and the prop shaft e.g DAF & SCANIA
On some of em you need to centre the lever and pull it out so that it locks into place.
And on some of them you don’t need to do anything as it will reset automatically above a set speed, although I like to reset it myself just to be sure.
Coffeeholic:
And on some of them you don’t need to do anything as it will reset automatically above a set speed
not if the handle isn’t returned to centre it wont!
Driveroneuk:
Coffeeholic:
And on some of them you don’t need to do anything as it will reset automatically above a set speednot if the handle isn’t returned to centre it wont!
But I suspect he means the “Push Button” ones, and they DO 
I’ve never come accross a push button one in all the variety of trailers i’ve seen from brand new to 30 yr old tandems. … and i’ve seen some, upto 8 a day sometimes.
Not saying they don’t exist, just i aint seen one.
Driveroneuk:
I’ve never come accross a push button one in all the variety of trailers i’ve seen from brand new to 30 yr old tandems. … and i’ve seen some, upto 8 a day sometimes.Not saying they don’t exist, just i aint seen one.
I have, on a Bass Brewers urban artic trailer.
Our Schmidt curtainsiders have a leveller lever on them.
To alter the height of the trailer, for a dock for example, you push the lever in, it clicks. You then rotate the lever one way to lift, the other way to lower. The lever is spring loaded towards the centre which is the ‘lock to set height’ position.
To reset the trailer to travelling height you pull the lever back out. It’s supposed to pop out automatically at about 10kph, if you forget to reset it yourself. However I personally wouldn’t trust it and always double check, if I don’t forget. 
City Link and the Post Office (on some trailers) have the push button system
Fords mega trailers have a similar system with buttons to select 'mega" travel height or “Regular” 
There are a good number of skellies out there with the push button system on. Be careful, though, they don’t all self-level if you drive off with the air dumped… 
The only trailer ive had with a button instead of a lever was that lowloader i had when i did my last diary, you pushed the button to dump all the air and pulled it to return to normal ride height.
The trailers im using now have a lever for adjusting and normal, a button to lift the tag (front axle of three) and a lock the rear steer button (when reversing) as well as the shunt and park brake, its like the cockpit of a bloody 747 under there i tell you
Off on a tangent a bit but seeing as were on about ride heights … I wish they would duplicate the remote pad by the seat onto the dashboard so you didnt have to lean down and to one side (and some you even have to open the door a bit too) whilst reversing under/driving from a trailer (i hate removing it from its holder as i wrap the lead around the pad so i dont keep treading on it)
I had 2 push buttons on my skelly. Pull them both out the air dumps so you have a good tipping slope. Push them in and the front and centre axle lift off the ground. It really confused the muppets at the Humber bridge when I went over as a 40 tonne 3 axle artic 
The axles all so reset themselves when you loaded the tank.
Lucy:
…they don’t all self-level if you drive off with the air dumped…
Last company i worked for had 4 new Fruehauf stepframe bathtubs back in '99 which all had the push-button type. The button was the same style as the handbrake/shunt buttons, but i seem to remember it also had a bar across the back of it pulling two rods instead of just the one. Anyways, this helped a bit when tipping in low sheds etc as it gave a slightly steeper tipping angle. You soon knew about it if you left it dumped though, as the ride was horrific (seat back kept banging you in the back!) and the brakes were even horrific-er Pulled up several times a few hundred yards out of farm entrances to jump out and push it back in!
montana man:
Driveroneuk:
Coffeeholic:
And on some of them you don’t need to do anything as it will reset automatically above a set speednot if the handle isn’t returned to centre it wont!
But I suspect he means the “Push Button” ones, and they DO
I actually meant ones with handles. The type that you push the handle in and turn it left or right to raise and lower the suspension. When it is at the correct height you release the handle and it returns to the centre, still pushed in. There is no way of leaving it turned. If you forget to re-set the suspension it does it when you drive away and reach a certain speed. Sorted.
Driveroneuk:
I’ve never come accross a push button one in all the variety of trailers i’ve seen from brand new to 30 yr old tandems. … and i’ve seen some, upto 8 a day sometimes.Not saying they don’t exist, just i aint seen one.
go to Tesco
Coffeeholic:
turn it left or right to raise and lower the suspension. When it is at the correct height you release the handle and it returns to the centre, still pushed in. There is no way of leaving it turned. If you forget to re-set the suspension it does it when you drive away and reach a certain speed. Sorted.
Some levers will remain in the turned position.
But agree what you say re self-levelling etc. applies to the majority of trailers. 
Driveroneuk:
Coffeeholic:
turn it left or right to raise and lower the suspension. When it is at the correct height you release the handle and it returns to the centre, still pushed in. There is no way of leaving it turned. If you forget to re-set the suspension it does it when you drive away and reach a certain speed. Sorted.Some levers will remain in the turned position.
Yes I know but I wasn’t talking about those type, I explained which type I meant in the post you quoted. 