Got a tweet from the Warrington Guardian website earlier where a lorry with trailer which was labelled up as 14’9 and the bridge being also 14’9. My question is who’s at fault?
@paulfromwire on Twitter
paulfromwire:
Got a tweet from the Warrington Guardian website earlier where a lorry with trailer which was labelled up as 14’9 and the bridge being also 14’9. My question is who’s at fault?@paulfromwire on Twitter
When trailers are labeled up as 14’9" high, it’ll usually say “based on a 1250mm 5th wheel height” or similar. Now, should the 5th wheel be a different height…
Scania’s for example raise by approx 3" when you lift the lift axle up, so a 14’9 trailer would be 15’ then.
But, assuming the 5th wheel is at the height the trailer was measured at, then I’d say the bridge is marked wrong.
That one 
You can see the trailer is marked at 14’9 so I guess it’s wrong, or he had his suspension up ■■? aFAIK Craptros doesn’t alter height when you lift the mid axle. Assuming you’ve not got you’re butty box on the bunk which is usually enough to keep it down
If thats the bridge that runs along the back of what used to be carrington wire then thats not the first time its been hit and probably won’t be the last …
billybigrig:
You can see the trailer is marked at 14’9 so I guess it’s wrong, or he had his suspension up ■■? aFAIK Craptros doesn’t alter height when you lift the mid axle. Assuming you’ve not got you’re butty box on the bunk which is usually enough to keep it down
I can’t read that, saved pic and blew it up and it’s still illegible
waynedl:
billybigrig:
You can see the trailer is marked at 14’9 so I guess it’s wrong, or he had his suspension up ■■? aFAIK Craptros doesn’t alter height when you lift the mid axle. Assuming you’ve not got you’re butty box on the bunk which is usually enough to keep it down
I can’t read that, saved pic and blew it up and it’s still illegible
Specsavers ■■?
HTH 
By the look of that, the nearest side of the bridge is lower than the other side.
I still think its amazing how such a small pin can hold a trailer through pretty much anything… Got to be one of the best inventions in all time along with the internal combustion engine.
Anyway it’s the drivers fault 100%.
FarnboroughBoy11:
I still think its amazing how such a small pin can hold a trailer through pretty much anything… Got to be one of the best inventions in all time along with the internal combustion engine.
Totally agree !
FarnboroughBoy11:
Anyway it’s the drivers fault 100%.
Disagree ! Although if you rattle through a bridge marked up as the same height as your trailer then you are in trouble. Even if there’s a difference of height in your favour you should be slowing down and checking it yourself… The reason I disagree is that usually they give you an inch at least on the trailer height and usually give you more on the bridge, but that said you shouldn’t really attempt a bridge that is the same advertised height as the trailer !
Pretty sure that’s Marsh House Lane Warrington the continuation of Padgate Lane
The Rylands Whitecross wire works used to be on there, it’s now a development of apartments.
That bridge gets battered on a regular basis
Kerbdog:
FarnboroughBoy11:
I still think its amazing how such a small pin can hold a trailer through pretty much anything… Got to be one of the best inventions in all time along with the internal combustion engine.Totally agree !
FarnboroughBoy11:
Anyway it’s the drivers fault 100%.Disagree ! Although if you rattle through a bridge marked up as the same height as your trailer then you are in trouble. Even if there’s a difference of height in your favour you should be slowing down and checking it yourself… The reason I disagree is that usually they give you an inch at least on the trailer height and usually give you more on the bridge, but that said you shouldn’t really attempt a bridge that is the same advertised height as the trailer !
and we’re off…
FarnboroughBoy11:
:lol:
Well lets be honest, we all have a go rather than go around because we know there’s a difference in the actual heights and also there is also a ‘lower’ button on the suspension to help you out… BUT, theres always a time that the CORRECT heights may be displayed.
just looked at the OP’s photo again and you have to say that the Forest Freight guy got quite a way through, must have been shifting a fair bit !
Kerbdog:
FarnboroughBoy11:
Anyway it’s the drivers fault 100%.Disagree ! Although if you rattle through a bridge marked up as the same height as your trailer then you are in trouble. Even if there’s a difference of height in your favour you should be slowing down and checking it yourself… The reason I disagree is that usually they give you an inch at least on the trailer height and usually give you more on the bridge, but that said you shouldn’t really attempt a bridge that is the same advertised height as the trailer !
The height marked on the bridge is not the height of the bridge but a maximum height for vehicles going under the bridge. So if a bridge is marked up at 14ft 9inches then you can get a 14ft 9 inch vehicle under it. If you can’t it’s not been marked up correctly.
This document covers the protocol for marking up the heights on bridges.
http://assets.dft.gov.uk/publications/low-bridges-prevention-bridge-strikes/bridges-over-highways.pdf
The clearance under bridges spanning public roads in the UK, below which low bridge
signing is required, is 16’-6” (5.03m). All bridges with a headroom of less than this, at
any point over a carriageway, should be signed in accordance with the guidance
given in Chapter 4 of the Traffic Signs Manual (TSM)2 , section 7. This will, in all
situations, allow a minimum safety margin of 3” or 0.1m (these are not equivalent
values but are each determined in accordance with the measurement guidelines).
The signed height at low bridges is referred to in this document as the (maximum)
safe vehicle height, as it represents the maximum height of vehicle/load combination
which can pass safely on the carriageway under the bridge without impacting on it,
allowing for vehicle (suspension) bounce, and safety tolerances.
waynedl:
paulfromwire:
Got a tweet from the Warrington Guardian website earlier where a lorry with trailer which was labelled up as 14’9 and the bridge being also 14’9. My question is who’s at fault?@paulfromwire on Twitter
When trailers are labeled up as 14’9" high, it’ll usually say “based on a 1250mm 5th wheel height” or similar. Now, should the 5th wheel be a different height…
Scania’s for example raise by approx 3" when you lift the lift axle up, so a 14’9 trailer would be 15’ then.
But, assuming the 5th wheel is at the height the trailer was measured at, then I’d say the bridge is marked wrong.
I had an Actros the other week and I’m positive it was marked higher than 1250mm, so when I worked it out it was 3" higher. Normal running for our trailers with the Volvo or Scania is 15’3 but with the Actros it was 15’6.
billybigrig:
Kerbdog:
FarnboroughBoy11:
I still think its amazing how such a small pin can hold a trailer through pretty much anything… Got to be one of the best inventions in all time along with the internal combustion engine.Totally agree !
FarnboroughBoy11:
Anyway it’s the drivers fault 100%.Disagree ! Although if you rattle through a bridge marked up as the same height as your trailer then you are in trouble. Even if there’s a difference of height in your favour you should be slowing down and checking it yourself… The reason I disagree is that usually they give you an inch at least on the trailer height and usually give you more on the bridge, but that said you shouldn’t really attempt a bridge that is the same advertised height as the trailer !
dCPC candidate speaks again
dts:
waynedl:
paulfromwire:
Got a tweet from the Warrington Guardian website earlier where a lorry with trailer which was labelled up as 14’9 and the bridge being also 14’9. My question is who’s at fault?@paulfromwire on Twitter
When trailers are labeled up as 14’9" high, it’ll usually say “based on a 1250mm 5th wheel height” or similar. Now, should the 5th wheel be a different height…
Scania’s for example raise by approx 3" when you lift the lift axle up, so a 14’9 trailer would be 15’ then.
But, assuming the 5th wheel is at the height the trailer was measured at, then I’d say the bridge is marked wrong.
I had an Actros the other week and I’m positive it was marked higher than 1250mm, so when I worked it out it was 3" higher. Normal running for our trailers with the Volvo or Scania is 15’3 but with the Actros it was 15’6.
Yes, 5th wheels can vary in height, hence most trailers say “14’9” based on a xxxxmm 5th wheel height"…
It is something we’ve got to be carefull of.