Trailer - Incorrect advice ref: Towing limits.

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Sat 27 Jan 2024 09:25
Trailer - Incorrect advice ref: Towing limits. - Tony Maris

Unfortunately, incorrect info was given by Dan Powell to a question “ What is the maximum weight we can tow?

I have a 2014 Toyota Land Cruiser. Its weight is 2.2 tonnes and the listed towing weight is 3.0 tonnes. We tow a horse box.

Half of our friends say the all up weight of the trailer cannot exceed the weight of the vehicle. Others say it is the maximum towing weight that matters.

We want to upgrade to an Equi-Trek box that is nearly 3 tonnes loaded

Who is correct?”

Dan replied “ Your friends are correct, the trailer must not exceed the weight of your car. Otherwise, it may result in poor stability when cornering or attempting to navigate a steep hill.


In my opinion, the towing capacity of your car should not be more than 85 per cent of your vehicle's kerb weight. The individual and combined weights of the vehicle and the trailer are among the most important things you need to know before towing. It’s vital that you stick to them; exceed them, and you’re breaking the law.

The Gross Vehicle Weight (GVW) or Maximum Authorised Mass (MAM) tells you how much a vehicle or a trailer can legally weigh in order to be used on the road, while the Gross Train Weight (GTW) or Gross Combination Weight (GCW), is the total, permitted weight of the vehicle, the trailer and everything it’s carrying. You can find these figures on the van or trailer’s chassis plate, in the handbook and sometimes on the V5C registration certificate.”

Whilst I agree a safe towing limit is 85% of the towing vehicles kerbweight, it is not a legal requirement.

Towing limit on a cat “B” licence depends on when you passed your test.

If you passed before 1 January 1997, you’re allowed to drive a vehicle and trailer combination with a maximum authorised mass (MAM) of 8,250kg.

If you passed your test on or after 1 January 1997, you can drive vehicles up to 3,500kg MAM with up to 8 passenger seats and with a trailer up to 750kg. You can also tow heavier trailers if the total MAM of the vehicle and trailer is no more than 3,500kg.

Edited by Tony Maris on 27/01/2024 at 09:26

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Sat 27 Jan 2024 10:09
Trailer - Incorrect advice ref: Towing limits. - skidpan

Back in the 90's I used to tow the Caterham behind my Golf GTi. The Golfs kerb weight was about 970 kg with a tow limit of 1200 kg. The total weight of the trailer, Caterham and spare wheels was about 1100 kg and I never had an issue. If I had relied on the 85% rule I would have needed a much bigger car than the Golf and some that I looked at had a similar towing limit.

It should be noted that I loaded the car and wheels on the trailer in exactly the same spot every time to get the correct 50 kg nose weight and also fitted a friction anti sway device.

Over 6 seasons and many 1000's of miles I never had an issue.

When we eventually swapped the Golf we bought another Golf, this time a TDi. That had a kerb weight closer to 1200 kg (making 85% still under what I was towing) but the tow limit had increased to 1300 kg. Just like the GTi we never had an issue.

The TDi was changed for a Mondeo TDCi. Despite having a higher kerb weight and a higher towing limit (1500 kg) on the couple of occasions I towed with it the combination never felt as stable. I believe to this day the short overhang of the Golfs made them more stable whereas the longer one of the Mondeo made the car feel a little uneasy.

Should add that back in the 90's very few people had the luxury of the huge pick up and SUV's people tend to use these days. Most ran ordinary hatchbacks but one chap on a real budget used his Lada Riva. One chap towed his Lotus Seven behind his Lotus Sunbeam and then arced them both in different classes. All he did to the Sunbeam was remove the towbar, stick on his race numbers and get it sideways at every opportunity.

But the Most spectacular combination was the chap who towed his Audi Quattro ex-Pike Peaks car behind his short wheelbase Quattro Sport. The race car and trailer would definitely been above 85% of the tow vehicle.

See this www.facebook.com/shelsleywalsh/posts/remember-the-.../

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Sat 27 Jan 2024 12:13
Trailer - Incorrect advice ref: Towing limits. - Brit_in_Germany

Isn't the towing weight dependent on the kerbweight and so depends on how much the Toyota is loaded.

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Sat 27 Jan 2024 13:25
Trailer - Incorrect advice ref: Towing limits. - RT

Dan is wrong! There no legal requirement for towing in relation to the car's kerbweight - there was for new drivers but it was abolished about 10 years ago along with the 3500 kg total limit.

The problem arises because a vehicle's towing limit applies to all types of trailer - some are more unstable than others so not going up to the towing limit is good in those cases - the caravanning clubs and their industry body NCC recommends that beginners shouldn't tow caravans exceeding the car's kerbweight but it is just a recommendation.

Other types of trailer, like race car trailers, have low centre of gravity and low side area so towing right up to the vehicle's towing limit is fine.

Edited by RT on 27/01/2024 at 13:29

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Sat 27 Jan 2024 14:41
Trailer - Incorrect advice ref: Towing limits. - Adampr

There's a difference between what's legal and what's right. The answer says not to tow more than 100%, not that it's illegal.

Anything above 85% requires a degree of skill and experience. Above 100% is silly unless you take specific steps to mitigate that risk.

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Sat 27 Jan 2024 15:31
Trailer - Incorrect advice ref: Towing limits. - RT

There's a difference between what's legal and what's right. The answer says not to tow more than 100%, not that it's illegal.

Anything above 85% requires a degree of skill and experience. Above 100% is silly unless you take specific steps to mitigate that risk.

That's simply too dogmatic - remember that in USA and Australia they'll tow Caravans (Travel Trailers) up to double the kerbweight and in the USA at higher speeds than we do.

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Sat 27 Jan 2024 19:09
Trailer - Incorrect advice ref: Towing limits. - Adampr

And both of those countries have much higher rates of vehicle fatalities than we do. Almost three times as much in the US.

Obviously, there are other factors at play (average speeds, remoteness of roads, likelihood of drink driving) but they clearly have a lower level of safety culture.

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Sun 28 Jan 2024 08:30
Trailer - Incorrect advice ref: Towing limits. - skidpan

Other types of trailer, like race car trailers, have low centre of gravity and low side area so towing right up to the vehicle's towing limit is fine.

Not all race car trailers are low. Mine, like many was enclosed because not only did it protect the car it also gave some protection to me on foul days in the paddock. It was not high enough to stand up in but had to be high enough to get a rack for the spare wheels above the car bonnet area. Worked a treat for many years.

When I eventually sold it (back problems made manoeuvring the trailer on the drive and through the garage a thing of the past) the chap who bought it (for his Westfield) mostly used it without the cover (easy enough since it was only held on with 4 bolts). At that point I went back to the road going class and track days and had the wife bring my kit in her car.

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Sun 28 Jan 2024 10:14
Trailer - Incorrect advice ref: Towing limits. - Andrew-T

Obviously, there are other factors at play (average speeds, remoteness of roads, likelihood of drink driving) but they clearly have a lower level of safety culture.

Not to mention straightness of roads and distance travelled !

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Sun 28 Jan 2024 11:03
Trailer - Incorrect advice ref: Towing limits. - gordonbennet

There are rules and there are advisories, as with most things its best not to jump in at the deep end and start towing huge trailers weighing more than 100% of the towing vehicle, most sensible people build up to towing higher weights and larger trailers through natural progression at their own pace learning what works and what doesn't along the way.

There's no hard and fast rule about what will make a good towing vehicle, other than it helps if the wheelbase of the towing vehicle is longer rather than shorter, the vehicle susbstantial enough to control the trailer and some common sense is applied to how the trailer is weighted where adequate weight is imposed on the towing socket, there is little more unstable than a trailer which is trying to lift itself off the towing attachment (tail wagging the dog), but too much weight imposed can have detrimental effects on any overrun braking systems which then can't move freely enough.

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Sun 28 Jan 2024 11:11
Trailer - Incorrect advice ref: Towing limits. - Terry W

A caravan above the weight of the towing car = tail wagging the dog.

In a straight line - accelerating or braking - there is limited impact on stability.

On cornering - most caravan brakes (UK) are overrun operated. Braking whilst cornering means (a) there is less compression on the overrun mechanism, and (b) the weight of the caravan will tend to push the rear of the car outwards.

Braking overall is compromised - Most caravans have non-ABS drum brakes operating typically on two wheel. Car probably has discs on all four. Weight transfer through the tow hitch means the tow car brakes may have potentially 2x their normal load.

Similarly tyres are compromised - there may now be (say) 6 tyres coping with grip to halt 3000kg (500kg/tyre) vs a car alone with 4 tyres and 1500kg (375kg/tyre). I suspect that a typical caravan tyre is also of lower spec than that fitted to the tow car.

I have no doubt that in normal circumstance a modern car has the power to tow a trailer twice its own weight, but in critical situations (accident, high winds, hitting a pothole, wet roads etc) it seriously lacks stability.

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Sun 28 Jan 2024 14:54
Trailer - Incorrect advice ref: Towing limits. - bathtub tom
I suspect that a typical caravan tyre is also of lower spec than that fitted to the tow car.

The caravans I had, had higher spec tyres than the tow car. Typically 6-ply as opposed to 4-ply on the car.

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Sun 28 Jan 2024 15:10
Trailer - Incorrect advice ref: Towing limits. - RT
I suspect that a typical caravan tyre is also of lower spec than that fitted to the tow car.

The caravans I had, had higher spec tyres than the tow car. Typically 6-ply as opposed to 4-ply on the car.

Most single axle caravans are on 8-ply "C" rated tyres these days - they're generally lower speed rated than car tyres but then car tyres are vastly over-rated for UK speed limits.

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Mon 29 Jan 2024 10:00
Trailer - Incorrect advice ref: Towing limits. - Bromptonaut

The 85/100% figures are recommendations for towing caravans.

Horseboxes, car trailers etc have different dynamics.

Exceeding the towing vehicle's plated limits for towing and/or Gross Train Weight are forms of overloading and likely to cause problems with the law and, in the event of an accident your insurer.

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Mon 29 Jan 2024 11:23
Trailer - Incorrect advice ref: Towing limits. - gordonbennet

The 85/100% figures are recommendations for towing caravans.

Horseboxes, car trailers etc have different dynamics.

Exceeding the towing vehicle's plated limits for towing and/or Gross Train Weight are forms of overloading and likely to cause problems with the law and, in the event of an accident your insurer.

Indeed, the typical horse trailer is one of the most stable trailers you will ever pull, as sure footed as a correctly weighted artic semi trailer outfit, the one we owned was Dutch built and had fully damped independent suspension, the ride inside that trailer was probably smoother than the Landcruiser i pulled it with.

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Mon 29 Jan 2024 11:26
Trailer - Incorrect advice ref: Towing limits. - skidpan

I suspect that a typical caravan tyre is also of lower spec than that fitted to the tow car.

The tyres on my car trailer were heavy duty Pirelli ones that had a load capacity well in excess of the load I expected to carry. They were not expensive either

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