CF, in reality unless some clueless clot positions a load in the most ridiculous of places on a trailer bed, on a typical 6 axle outfit it’s difficult to find an overloaded axle.
Where there can be issues is with small mid lift wheels on a 6x2 tractor which have a much lower max axle weight (eg as low as 4.6 tons), this is invariably down to poor positioning of a sliding fifth wheel and almost always down to the steering wheel operative in question not being in the least interested, a driver worth his/her salt would already have sussed out the ideal position if it was their regular steed not only for good weight distribution but for safer handling, for general usage vehicles the sweet spot is typically about the mid way point of the slider.
the maoster:
I will add that in the many years I have been driving I’ve never once queried as to how much a trailer weighs, .
I had in my head that the unit would be roughly 9t. I had no idea what a trailer would be.
More interesting tare weights when you get to specialised vehicles, my last car transporter tared off over 22 tons, don’t know how heavy each section was as the vehicle was designed only to operate as a complete vehicle.
Back when i was blond and road tax was charged on unladen weight,i shared a yard with some car transporter guys with wagon and drag type vehicles.
I had an F86 Volvo tractor unit and a 40ft/skelly with a castellated chassis.The rig was so light it was remarkable.I was not encouraged to use the trailer without a container as it could bend if you gave it a hard look.
I used to run at 32 tons on very little road tax while the car carriers had to pay loads more to tax theirs.
Gidders:
There was a time many moons ago when a vehicle’s road tax (VED) was determined by its unladen weight,if I recall correctly.
There was a time when all new vehicles went straight to the weighbridge so the unladen weight was known, and fixed to a plate or sticker.
That’s just too logical.Bearing in mind that weight distribution could also play havoc with a simplistic deduction of total unit and trailer tare weights to provide an overall payload figure.I’d doubt that my figures are a million miles away from the mark in the real world.
I will bring this to the attention of my boss. We load our milk tankers with 28500 liters of milk, which puts us at just a smidge under 44 ton gross. But thanks to CF I have just realised, that every time I drive down hill, I overload the tractor, and when I go uphill, I overload the trailer axles…
the maoster:
I will add that in the many years I have been driving I’ve never once queried as to how much a trailer weighs, .
I had in my head that the unit would be roughly 9t. I had no idea what a trailer would be.
More interesting tare weights when you get to specialised vehicles, my last car transporter tared off over 22 tons, don’t know how heavy each section was as the vehicle was designed only to operate as a complete vehicle.
Back when i was blond and road tax was charged on unladen weight,i shared a yard with some car transporter guys with wagon and drag type vehicles.
I had an F86 Volvo tractor unit and a 40ft/skelly with a castellated chassis.The rig was so light it was remarkable.I was not encouraged to use the trailer without a container as it could bend if you gave it a hard look.
I used to run at 32 tons on very little road tax while the car carriers had to pay loads more to tax theirs.
I’ve been pondering the days of 32 tons on 4 axles recently.
Back then i had a Leyland Buffalo and York 40ft trl, tared off at 10 tons, meaning a 21 ton load was no problem and could push it to 22 tons if there was a weighbridge close by to check axle weights.
The vehicles were light and cheap with only 4 axles so less drag and less damage to the roads*, better on fuel too.
Now we’re up to 44 tons and just about 6 or 7 tons more load, was the extra weight gain really worth it i’m not so sure, and the vehicles inflict immense damage on the roads as anywhere that sees lorries turning tight will have massive chunks torn out of the surface almost on a daily basis, let alone the subsidence issues now showing due to the unceasing pounding, anyone traversed the M25 recently near Potters Bar/Enfield on the limiter and tried to stay in the seat?
I remember when we went up to 38 tons i was on bulk tippers at the time, on 5 axles 38t wasn’t road tax up around £3200 in 1982 or whenever the new weight was allowed.
Operators spent a fortune having extra axles grafted onto existing trailers, which invariable fell apart due to never being designed to carry such weight or have such side forces exerted on the chassis as 3 fixed axles provides, plus iof you ever went near an axles weigher you’d find to your horror that the converters hadn’t taken weigth distribution into consideration, in one shocking encounter with an axle weigher at a farm i found the three trl axles loaded the rear axle weighed in at 12 tons, that went striaght off for further conversion soon as i returned with the news.
My gaffer of the time issued me with a new twin steer tractor in 84, taxed it for 6 axles for £1500 if my memory serves, but of course i couldn’t pull any of the existing tandem trailers with it due to tax banding.
Again, all that expense and trouble for the increase of what 3 tons in payload? was it worth it.
To this day i’m not so sure as we wouldn’t have been better off sticking at 32 tons max after all, for sure the roads would have been less damaged.
*remember the experts of the time telling us all how kind to the roads 6 axled lorries would be, any experts actually witnessed a fully loaded triaxle on tight curve
Juddian:
CF, in reality unless some clueless clot positions a load in the most ridiculous of places on a trailer bed, on a typical 6 axle outfit it’s difficult to find an overloaded axle.
Where there can be issues is with small mid lift wheels on a 6x2 tractor which have a much lower max axle weight (eg as low as 4.6 tons), this is invariably down to poor positioning of a sliding fifth wheel and almost always down to the steering wheel operative in question not being in the least interested, a driver worth his/her salt would already have sussed out the ideal position if it was their regular steed not only for good weight distribution but for safer handling, for general usage vehicles the sweet spot is typically about the mid way point of the slider.
To be fair it’s probably relatively less difficult to exceed the unit’s or trailer’s max gross than an individual unit axle weight assuming a simple gross minus tare combination weight calculation.At best requiring a few trips to a weighbridge to redistribute the load to increase the weight on the trailer axles or vice versa.
I’d be very sceptical of the calculations for a premium type 4x2 unit pulling a triaxle in that regard.Its probably fair to say that trying to max out the payload weight based on the combination’s tare weight is going to be more bother and riskier than it’s worth in many cases.
The days of minimum weight plastic day cabbed swb units and flat trailers and rates based on maxing out payload weight have probably long gone.
But would be interesting to see a max payload comparison of 3 + 2 configuration artic v 3 + 3 in that regard.Probably not much in it at the end of the day and probably less chance of overloading the unit at 40t max than 44t.While 2 + 3 at 40t gross is probably the worst of all worlds.
As others have said, if you need to know what you can carry, you need to tare the complete outfit on a weighbridge, before you load it.
I would reckon that the outfit described by the OP would be able to carry 24 tons comfortably, and possibly 25.
There is a huge variety in the unladen weight of trucks and trailers.
I run a Scania 480 tag, with a hydraulic pump and tank, but devoid of any bells and whistles. No wind kit, no banks of spotlights etc. Coupled to a triaxle flat, heavy duty, with 20 log pins, I can just scrape 27 tons of payload, others, with light units and trailers, can, as Dan said get 29> tons.
