First let me say that I wasn't there when your instructor gave you this explanation. It is possible that you miss-understood, hearing what you needed to hear so tht you could go about your business. But I also say this:-
9 out of 10 people that we have purchase a trailer from us that have been through the 'Trailer Test' we have to re-train in order to make them safe towing restored trailer caravans often worth in excess of £30k.
Most of them have little idea of how to load a trailer correctly for balance; they have little idea of how to reverse a trailer properly; they know very little about trailer safety. And most have the road sense of a rutting toad.
By the same instance a lot of folk that pass their driving test can't drive they have just been taught how to pass their test.
Sorry I don't wish to insult new Drivers or drivers that have just passed their TT and I am sure that most folk on here don't fit that description.
Now lets get back to the law
It is written on the DVLA web site - it is very clear
There are fuller descriptions on .gov but you need a degree in motoring law to understand the correct interpretation.
NTTA website has a good description of the law as it applies to tin tent pullers and this will give a good idea of how to interprate the law for other tuggers.
Vehicle construction and use is also a good source of information if you wanna go in depth on your tugs abilities.
If the law allowed, as some believe, you to pull a trailer of say MAM=3500kgs behind a vehicle that was not capable of taking the full possible weight of that trailer then the law would also have to allow a car driver to drive a 7500kgs truck because empty it only weighed 3500kgs.
It would also mean that a every vehicle (private or commercial) that was carrying a load of any sort on the public highway when pulled for a check would have to be weighed.
No this doesn’t make sense
Your legalities for loads are set on what is possible not what is actual for the equipment you are using.
Commercial OP's will know that you can have any vehicle re-plated for a lesser weight under certain circumstances. I used to have a 9 ton truck down plated by MOT to 7.5. I have had busses re-assessed for conversion to Motor Homes...........Trailers are no different; A manu can plate a trailer for the maximum load it is to carry and most manu's will do so on purchase. This is perfectly7 legal and correct.
It also has to be said that, agree or not, law's are passed often because of a necessity. A lot of the time driving laws are upgraded or changed because of the constantly growing number of idiotic drivers behavior and lack of responsibility on the road.
How many times have you seen tin tenters with overloaded or wrongly balanced trailers?
How many times have you followed a trailer and watched it wagging it's tail?
How many times have you seen a driver unable to reverse a load that is trailerised? (lack of proper control)
How many accidents with trailers are caused by lack of maintenance?
I could go on
I often tow 'illegal' loads..............there are laws to govern that as well.
Laws that allow me to have a train length of over 60ft; laws that allow me to tug 'overweight' or 'overwide' etc
There are even laws that allows me to drive a vehicle for which I do not hold a license
And, as far as trailer laws are concerned it really PISSES ME OFF that every few years the law comes down even harder because of the few idiots that don't or won't comply
The next proposed batch is the private trailer MOT..............As far as our procedures are concerned it makes little difference as we will never pass a trailer on to a customer that is unsafe for the road and we will never let a customer leave here with a rig that is not up to it. We even do our best to make sure that the driver is competent with the outfit he has just purchased. But the infrastructure that will need to be in place for these regulations will cost us BIG TIME and that is a cost that we will have difficulty passing on to the customer
Unfortunately, these laws are becoming essential
Sorry folk. I'll get down off my soapbox now.
But like it or not; you cannot legally tow a trailer plated @ 3500kgs behind a truck that is rated @ 2800kgs. Loaded or not. Furthermore I know of no 4x4 in this country (unless specially adapted) that can legally tow a load in excess of 3500kgs (see special construction and use of motor vehicles) But I see many doing so
But then again why would you need to? There are plenty vehicles that can legally tow these weights. We have 2............they are called medium duty vehicles............small trucks. Like a 5.5 ton Dodge and a 7.5 ton Merc