We are looking at upgrading our current van. Can anybody explain what are the major factors that make a van 'tow well'? Is it the tow ball weight or something else or a number of things. The weight we are looking at is between 2.5t and 3t.
Within reason, the more weight on the ball the better they tow. Vans tend to load with an increase in ball weight so allow a little headroom so as not to overload the ball weight figure on the tug.
For safety keep weight away from the ends. That means centre kitchen, no more than one spare wheel on the rear and don't add things to the bumper bar or draw bar.
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PeterD Nissan Navara D23 diesel auto, Spaceland pop-top Retired radio and electronics technician. NSW Central Coast.
I agree with Legendts. I have an old Compass 18' A photo is in "show us your rig" you will see that the axle is an unusual distance to the rear but it tows and manouvres really well.
Weight distribution and centre of gravity are the main ingredients for towing small pig type trailers, (caravans). Most people think they have the weight and centre of gravity balances right, but in most sway induced rollovers, the weight may be spread between the wheels evenly back to front, but more weight to one side. No matter what tyre pressure you have unless they have greatly varying pressures, when sway inertia enters the equation and there is more weight to one side, the sway will be rapid and extremely hard to handle. It only needs to be a few kilo's for it to have an effect. Unless your rig is balanced, no matter what you do there's more than a 60% chance you will go over in even a small sway situation. But if weight is distributed evenly on across and the length of the van, you have a 60% chance of controlling it.
An unbalanced van and a change in wind direction or velocity at speed, is a recipe for disaster ahead.
-- Edited by native pepper on Thursday 1st of May 2014 04:13:50 PM
Low yaw inertia (centralised weight and shorter van), which is NOT the same as centre of gravity).
Low hitch overhang. The hitch needs to be as close to the rear axle as possible. Semi trailers and 5th wheelers are stable because the hitch is over or in front of the axle.
Long wheel base in the tug.
Higher tug mass compared with the van.
Here is a quote...."Higher tug mass compared with the van."
car manufacturers say you can tow 3 tonne with this vehicle....What a load of hogwash is what I say.
Your tug vehicle should weigh far more than the towed vehicle.
I have been in the outback for some time now and seen tripple trailer roadtrains pass (in both directions) causing caravans to nearly get swept off the road once the airstream hits them. And this is mainly because of a Mazda twin cab (or similar) is towing a 2850kg van. And then you have these 5th wheelers being pulled by similar vehicles.
You mark my words...these 5th wheelers are going to be required to have a small truck of at least 4 tonne to tow them( once authorities and Insurance Companies see the claims comming in. I also see that 18 year old drivers that just got their licence last week being required to get a higher grade of licence and experience before they can drive like this.
Here is a quote...."Higher tug mass compared with the van."
car manufacturers say you can tow 3 tonne with this vehicle....What a load of hogwash is what I say.
Your tug vehicle should weigh far more than the towed vehicle.
I have been in the outback for some time now and seen tripple trailer roadtrains pass (in both directions) causing caravans to nearly get swept off the road once the airstream hits them. And this is mainly because of a Mazda twin cab (or similar) is towing a 2850kg van. And then you have these 5th wheelers being pulled by similar vehicles.
You mark my words...these 5th wheelers are going to be required to have a small truck of at least 4 tonne to tow them( once authorities and Insurance Companies see the claims comming in. I also see that 18 year old drivers that just got their licence last week being required to get a higher grade of licence and experience before they can drive like this.
AM I WRONG???
It's the configuration of the towing vehicle which determines it's ability to tow properly, not the actual mass weight. A prime mover can be less than 10% of it's towing load, but be completely stable because of the way they are set up and the power they put to the wheels. Rt's I drive, have weights between 135 and 150 tonnes. The prime movers are below 10 tonne, full of fuel. Under 90% of conditions they are completely controllable and not subject to wind shear, on most occasions. As you describe, when passing vans, all you see in the mirrors is violently swaying rigs careering down the road as the wind pressure easily pushes them aside.
A car, is designed to carry people and is not set up for towing anything which would be bigger than it's weight, so you are right in that respect. When you look at the difference in configuration between a semi and a van/5th wheeler being towed by a passenger vehicle, it's easy to see why so many end up as wood chips and scrap metal. Caravans and 5th wheelers, are just big wind catchers, high, light and badly designed for towing.
The safest design for a caravan, is a dog trailer configuration, where all the weight is evenly distributed and balance points on the four corners of the trailer. Vans, have their wheels situated in the middle which is perfect recipe for introducing sway, wind driven inertia and ability to unbalance the load. You hit the brakes with a van behind you and all the weight is thrown forward onto the tow ball, making the car unstable and uncontrollable. From that, there is only on conclusion, disaster when faced with situations where you have to take evasive actions. When that happens, 9 out of 10 vans fail to respond in the right way and end up dragging the tow vehicle into a disaster, as they go over.
Caravans and 5th wheelers, towed by passenger vehicles and that includes utes, should be restricted to 80kph, over that if anything goes wrong, the outcomes are always disastrous.
Most modern caravans have the axles set to the rear of centre. The big trick is to load the car heavier than the van, and then try to keep all the van weight over the wheels and in front of the wheels. Leveller bars or stabilisers will take care of the balance.
The modern vans also put a lot of weight out the back of the caravan. The modular shower cubicle, the toilet, vanity cupboard and hand basin, washing machine and drier. That's a lot of weight before you even load the van. Add to that water tanks carrying more than 100 litres, gas bottles, furniture and fittings, and the stuff you put in the van to travel. It's all about the weight and where it is.
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20ft Roma caravan - Mercedes Benz Sprinter - SA-based at the moment. Transport has no borders.
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