Usually quoted as x amount from x 5th wheel height.
So how do I know what 5th wheel height is?
Is there a standard height when suspension is at road running level?
I doubt there is a standard 5th wheel height…For your own peace of mind,you could always measure it,and then do the sums.
Most “standard” uk spec units will have a 5th wheel plate height of around 1.2M. I’m talking here about the sort of units you see everyday.
We seem to have an obsession in this country of specing sliders of which most are never moved. I know you can spec low height sliders but these are rare.
Look at most european units and you will find that they run a lower profile 5th wheel, look how close to the mudguards the trailer body is, and 70 series tyres and can get their plate height down to around 1.0M. Go for lower profile mega tyres and you can get it down to around 0.9M.
I’m sure a lot of this must be to do with the 4.0M bridge heights that most have to deal with whereas in jolly old blighty we generally aren’t restricted so our specs have hardly changed since the 60s regarding 5th wheel heights or trailer chassis design for that matter.
The classic example is the skelly. Go to holland and they are getting highcube boxes on trailers at bang on 4.0M where as we in this country we run standard boxes at 4.1M or high cubes at 4.4m.
One other thing to bear in mind is that most 6 wheel units will push the 5th wheel plate up a couple of inches when the 3rd axle is lifted. Scania in particular are bad for this.
Cheers
Neilf
dar1976:
Usually quoted as x amount from x 5th wheel height.So how do I know what 5th wheel height is?
You could paint horizontal white lines on a pair of overalls at 10 cm intervals then stand behind the 5th wheel and count the white lines from the ground to the level of the 5th wheel.
Or
You could use a tape measure 
I was expecting someone to make a tape measure comment.
But just wondered if there was a standard ride height for fifth wheels.
Apparently not.
Thanks for the input guys.
Just on trailer heights if you take a trailer out with a sixteen ft height limit would you take it under a 16 ft height limited bridge not sureon that one personaly I would probably lower the susspesion or avoid it in the first place.
dar1976:
Usually quoted as x amount from x 5th wheel height.So how do I know what 5th wheel height is?
Is there a standard height when suspension is at road running level?
Hi Dean,
As an general average, I’d say that 1,250mm is in the ball park, but it’s not set in stone…
I must agree with tachograph and suggest that you use a tape measure, because this is something that you really don’t want to get wrong.
Do it by eye.
Saaamon:
Do it by eye.
If you stand on your head its more accurate.
Don’t forget if you drive a Scania with a mid - lift axle the fifth wheel will rise by 40mm if you actually lift the axle