BUYING AN NEW TOW VEHICLE – A BEGINNERS GUIDE.

At Truck Friendly we are often asked, “What is the best tow vehicle for a caravan”?

HOW TO FIND THE BEST TOW VEHICLE.?

The answer is that there is no one vehicle that suits all circumstances and all caravans. However, we have put together the main things to consider when purchasing a new tow vehicle for your caravan.

Match the caravan to the tow vehicle, or the tow vehicle to the caravan. It is your preference but you do need to match them.

POWER and TORQUE

This is often one of the main areas of discussion on social media when this question is asked. However, as you will quickly see there is far more considerations to keep in mind.

Simply – The more TORQUE an engine has, the better it is suited for towing heavy trailers / caravans and for climbing steep grades. It is usually measured at the engine revolutions that provide the most output.

HORSEPOWER on the other hand measures the engines overall performance across all conditions.

High horsepower and high torque engines are needed to tow heavy vans and maintain speeds up hills.

The new tow vehicle must have the power and torque to tow the caravan or camper trailer that you have or intend to purchase. Then have some extra in reserve.

While the V8 Diesel is still the preferred option for many large caravan owners the petrol models are starting to make their mark.

Large diesel motors usually have the torque to help maintain power when needed and the reliability proven over the years. It is not uncommon to see big diesel tow vehicles with several hundred thousand kilometres on the speedo still happily pulling big vans around Australia.

Always be cautious of the smaller motors that rely on turbo chargers to run motors at maximum power as some may struggle when sheer grunt is needed.

Motors and models are always changing so do your homework by checking and comparing torque and power ratings, while asking around for recommendations.

SIZE

Every family have their own needs, and carry different amounts of people, luggage, camping gear and, are required to tow different size and weight caravans or camper trailers.

Family needs change and it is personal choice as to whether you feel the need for a 2-, 5- or 8-seater vehicle to fit all the family and friends in. Extra space is needed for children’s car seats.

The more seats you have is usually at the expense of cargo space, so the dual cab utes provide a happy medium for many younger families.

Like all vehicles they do have their limitations, and many can tow larger vans and carry a tonne of load but DEFINITELY NOT at the same time. This article explains more on that subject. https://www.facebook.com/truckfriendly.com.au/photos/a.343242826371704/692992531396730

For safe towing it is strongly recommended that the loaded TOW VEHICLE SHOULD BE HEAVIER THAN THE CARAVAN that it is towing. A light tow vehicle can be thrown around by a heavy caravan and result in dangerous caravan sway and rollover.

RATINGS

Every vehicle has its towing and weight limits. These are expressed in the limits placed by the manufacturer for that particular vehicle make and model.

Exceeding these limits may mean your vehicle is overloaded, unroadworthy and therefore not permitted on the roads. Almost all insurance policies will have an exclusion of cover for any vehicle that is overloaded and / or a vehicle that is unroadworthy.

What is the ATM (Aggregate Trailer Mass) and TBM (Tow Ball Mass) of the caravan that you want to tow or purchase, now or in the future?

The tow vehicle will have many ratings to cover different aspects of the vehicle, however the following are the main ratings.

GVM (Gross Vehicle Mass) This is this maximum weight that the tow vehicle can weight, fully loaded and includes ALL accessories and after market kits, canopy, bull bar, roof racks, luggage, camping gear, fridge, fridge slide, tow hitch and all people that will travel in the vehicle including driver and passengers. It will also include the tow ball weight of the caravan once connected.

TBW (Tow Ball Weight) This is the maximum download that the vehicle can have on the tow ball of the vehicle. It should also be noted that the tow bar itself must comply with the same rating or the lesser of the two will apply. What is the weight of the tow ball on the caravan?

CAUTION – some vehicles may have lighter towbars fitted so please check prior to connecting your van.

GCM (Gross Combined Mass) This is the maximum weight the tow vehicle can safety move. It includes the tow vehicle, fully loaded (GVM) plus the fully loaded caravan (ATM). Follow the link above for an explanation regarding the dual cab utes and explanation of GCM ratings.

Many do not take the GCM into consideration when adding boats and other accessories to their vehicle loads.

For example: – The average dual cab ute has a weight of approx. 2,200 (Kerb Weight), a GVM of 3,200 kgs and a GCM of 6,000 kgs.

This means, with a 6,000 GCM, if you want to tow a 3,500 kg caravan with the dual cab ute you only have 2,500 kgs (6,000 less 3,500 = 2,500) for the vehicle and all load and passengers. If the vehicle itself weights 2,200 kgs then there is only 300 kgs left for all load, passengers and accessories. (6,000 less 3,500 and less vehicle weight of 2,200 = 300.)

That boat that many are carrying on the roof may well be illegal in many cases.

The Tow Ball Weight will transfer to the tow vehicle once connected but for ease of GCM calculations the GVM and ATM can be used initially.

Once connected, the Tow Ball Weight becomes part of the tow vehicles GVM and the caravan / trailer GTM (Gross Combined Mass) is used. I added this for the purists who will point it out if I don’t.

Buy a tow vehicle that fits your needs and that of what you want to tow.

It can be very expensive selling your vehicles and upgrading because you failed to do your homework to start with.

SHAPE and DESIGN

Shape and design may sound an unusual thing to consider for a tow vehicle, however the shape or design can have a very high impact on the stable towing ability of the vehicle.

For example, THE BEST DESIGN IS TO HAVE THE TOW BALL AS CLOSE AS POSSIBLE TO THE REAR AXLE.

The 5th wheeler caravans are becoming more popular, in part, because they are far more stable than a traditional ‘pig’ trailer caravan design. The 5th wheeler trailer attachments directly over the rear axle provides the most stable connection and reduces dangerous caravan sway to negligible levels in most cases. This is similar to the semi-trailers used extensively throughout the world.

Any good tow vehicle will have a short overhang past the rear axle and as short a tow hitch as practical. This will help reduce the impact of caravan sway on the caravan and on the tow vehicle.

The longer the distance the more pronounced any movement will be once sway starts.

The longer the overhang to the tow hitch, the more leverage the weight of the caravan will impact the rear suspension and conversely raise weight off the front suspension, reducing traction, steering and potentially overloading the rear axle and suspension maximum weights.

SUSPENSION

The caravan will attach to the tow hitch at the rear of the tow vehicle. This will apply heavy weights at the point of attachment that will lever the front of the vehicle upwards as a result. The more the rear suspension is compressed the higher the front will lift.

If the tow vehicle is not designed to have such a heavy load on the rear tow bal,l the vehicle can easily become unstable and dangerous to drive and control with reduced traction and steering.

IT IS STRONGLY RECOMMENDED TO CHOSE A VEHICLE WITH THE SUSPENSION TO SAFELY HANDLE SUCH LOADS. A suspension upgrade by a professional may be the answer in some cases.

Weight Distribution Hitches are common accessories for caravanners, and they help transfer some of the rear axle weight to the front axle of the tow vehicle for more level, stable and safer towing. HOWEVER, in many cases they are wrongly used to hide a bigger problem, of faulty or inadequate suspension. The faulty suspension will still be there.

FIX THE PROBLEM, NOT THE SYMPTOM.

Many manufacturers do not recommend the use of weight distribution hitches on their vehicles, while others state they are required for towing heavy trailers. Check with your manufacturers recommendations as your insurance may be voided if not following recommendations.

Check with a suspension expert before using any weight distribution hitch. Overstressing the WDH can cause chassis damage.

There are many things to consider when matching a new tow vehicle with your and your family needs and the caravan that you intend to tow safely and legally.

I trust that this article has helped you understand some of the things you need to consider to safety enjoy your caravanning experience.

Stay safe.

Ken Wilson

#truckfriendly

www.truckfriendly.com.au

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