Articles by David Morley

Q: How to work out fuel consumption?A: When you look at the official government website, fuel consumption is usually expressed as a number of litres of fuel per 100km travelled. But it is also better understood by some (often older folk who remember miles per gallon) when it’s expressed as a number of kilometres covered per litre of fuel. Either way, it’s pretty simple mathematics.In an age when even budget new cars have trip computers to offer up an average fuel consumption number on the run, it’s tempting to assume that that’s all you need to check.Which is fine if you’re not too concerned about pin-point accuracy, because on-board trip computers aren’t as accurate as many people think.These computers typically measure the amount of air that enters the engine (via an engine sensor) and then refer to a set of tables that gives it the corresponding amount of fuel.Unfortunately, this isn’t always a totally accurate method and while it’s convenient and close enough for most, it’s not the way a scientist would measure fuel consumption.That same scientist would resort to basic mathematics, and regardless of whether it’s to calculate how many litres petrol per kilometre, how many litres per 100km or even kilometres per litre, it’s all the same fundamental but specific fuel consumption formula.So, here’s how it works: We have two known factors here. The first is the number of kilometres travelled (assuming you reset your trip meter when you last fuelled up) and the number of litres you’ve just added to the tank to bring the car back to full.To keep the mathematics simple, let’s say you’ve travelled 500km from the last fill and added 40 litres to bring the tank back to full.If you want to know the litres per 100km, you divide the number of litres by the number of 100km chunks of travel (in this case, five - 500 divided by 100). When you divide 40 by five, you get eight which means you’ve used eight litres per 100km travelled.You’ll probably find your chunks of 100km aren’t a nice, round number, but it works with decimal places, too. So, if you covered 560km for those same 40 litres, the equation would be 40 divided by 5.6 (for a figure of 7.14 litres per 100km).But what if you want to know the kilometres per litre you’ve achieved on the same trip? Now the equation becomes the distance travelled divided by the litres consumed.That is: 500 divided by 40, which means you’ve covered 12.5 kilometres for every litre used.While this is often a more accurate method that relying on the trip computer, there are still variables.Odometers are not always spot-on accurate, and while fuel pumps are regularly checked for accuracy, some will still fill a car more completely than others before 'clicking off'.Perhaps the forecourt where you’re filling isn’t perfectly flat. Heck, even ambient temperature can have an effect on how much physical space petrol occupies.The next step, of course, is how to work out fuel cost as opposed to the bald numbers. Again, this is pretty simple and based on our previous figures and a per-litre fuel price of $1.80, our car that achieves 8.0 litres per 100km costs $14.40 to cover that distance. Per kilometre, that works out to 14.4 cents.In any case, the biggest factor determining fuel economy is your driving style. It doesn’t matter whether you drive a car, ute, SUV or truck, or whether it’s powered by petrol, diesel, gas (LPG) or it’s a hybrid, the best way to save fuel is to drive smoothly and use as little throttle as possible.The other number that can be a bit misleading in fuel consumption terms is the official government-test figure that is on the windscreen of brand-new cars in the showroom. These figures equate to a highway cycle test, an urban cycle test and a combination of those two tests.The tests are exactly the same for each and every vehicle sold in Australia, but while they can therefore be compared against each other, in terms of real-world fuel consumption results, they are a long way off.Broadly speaking, in normal use, you’ll never match those numbers, let alone beat them. Why? Because car makes understand the testing procedure intimately and actually design their cars to do well in the test, often at the expense of real-world driveability and fuel economy thanks to super-tall gearing and other measures.You can also thank these tests for the often-annoying stop-start function on new cars which saves precious drops on the test, but is something many owners switch off every time they drive the car.That’s why the car that suggests (on the test sticker) that it can cover 100km on a highway on just eight litres of fuel, will probably require more like 10 litres to actually do so outside the test lab.Use these figures only as an apples versus apples measurement yardstick against competing makes and models where they’re relevant, and not as a real-world guide to consumption.

If you’ve ever been around a group of caravanners, the term WDH will probably have cropped up. But what is a WDH and do you need one?WDH stands for Weight Distribution Hitch, but they’re also known as caravan ride levellers, a load distribution hitch, weight distribution bars, caravan levelling devices, and more, but they’re all more or less the same thing and operate on the same principles.So, how do weight distribution hitches work? Fundamentally, a WDH is used to make a tow-car and its load (trailer, caravan, whatever) more stable by improving the weight distribution of the whole combination.It does that by shifting some of the weight from the rear axle of the towing vehicle to the front axle, and some of the weight back on to the trailer’s axle(s).In the process, this means the car will steer better and have more grip at the front wheels for braking. The safety implications of that are obvious.Standard towing hitches for caravans do not have these features, so a WDH is something you need to specify when buying a van or purchase later.The actual mechanics of the WDH are pretty straightforward. Fundamentally, you’re reducing the effect of the towball downweight applied by the trailer.The WDH achieves this by providing a levering effect that raises the rear of the tow-car and lowers the front.It does that via couplings and sprung torsion bars that link the car to the trailer yet still allow articulation at the tow-ball.Most WDHs consist of a tow-ball tongue with the necessary attachment points, the torsion bars that run between the vehicle and trailer, adjustable chains to allow for different torsional loads, and a set of heavy-duty clamps that attach to the trailer’s A frame to accept the chains.The mistake a lot of users make is to assume that a WDH hitch will also act as a sway control or caravan sway bars as they’re also known.Certainly, by making the weight distribution of a towing combination better, a WDH makes every aspect of towing safer, but a specific cure for trailer sway they are not.Some WDHs incorporate a sway controller into their design, but not all, so make sure you know what you’re buying.There are no hard and fast rules about using a WDH or not, but there’s reasonable consensus out there that for caravan towing under about 2000kg or for a van less than five metres, there’s not really as much benefit from a WDH.The average camper trailer should not really need a WDH. Also, the rule of thumb goes, if the tow-car’s front suspension doesn’t rise by more than about 20mm with the trailer hooked up, and the rear suspension doesn’t fall by at least the same 20mm, you don’t really need a WDH.On a 4WD with heavy suspension, you might find very little deflection of the suspension. Even then, repacking the caravan to better distribute the weight is your first step, rather than rushing out and buying a WDH.Clearly, in a lot of cases, towing without weight distribution hitch is not the end of the world.Some carmakers don’t recommend WDHs either, and, in fact, some go as far as to void your warranty if you use one and damage results.Typically, some cars with air suspension aren’t recommended for a WDH, as the device messes up the car’s factory self-levelling function.Even with a good WDH towing is not always hassle free, and the WDH itself imposes some considerations. One of these is noise, and the levers under tension can produce all sort of nasty creaks and groans.A WDH is also not as good off-road where the greater articulation required at the towball generally rules them out.That said, when it comes to the off-road oriented pin-type DO35 hitch problems off-road can be avoided by ensuring the towball maximum weight of 350kg is not exceeded and that full articulation is maintained.The DO35 can be configured to work with at least two Hayman Reese WDHs.It’s for the same articulation reasons that most WDH manufacturers recommend that you disconnect the WDH when crossing spoon drains or deep gutters and driveways. This is probably the single greatest bug-bear of the whole WDH experience.You’ll often see online forums posing questions about Andersen weight distribution hitch problems, Alko hitch problems, McHitch problems and general questions about all brands including well-known gear such as Hayman Reese.In many cases, the root causes of these problems lie in incorrect use and fitment of the hitch rather than any design or manufacturing flaw, and it’s an absolute fact that correctly and safely using a WDH hitch requires some familiarisation.Which means, of course, that the best weight distribution hitch Australia wide is the one that suits your car and trailer and is the one you know how to use effectively and safely.All the different types and brands use the same basic engineering principles, but a quality brand is crucial in something with the potential to completely change a vehicle’s dynamics. Don’t be afraid to ask question when shopping for a WDH and don’t be surprised if you get a lot of different opinions on the value of such a thing.

As we head towards an EV future, the concept of a portable EV charger becomes a fairly broad one.

Q: One of the hot-button topics right now with rising fuel prices is how to improve fuel economy?A: Believe it or not, there are plenty of things you can do or change that can have a noticeable effect on your car’s fuel economy. Most of them are simple, most of them cost nothing, and they can all stretch each precious litre of fuel a little farther.1. Probably the most effective way to save fuel is to modify the way you drive. How fast you accelerate and how suddenly you brake are doubtless the biggest factors in how much fuel you’ll use.Drive smoothly, anticipate red lights and traffic snarls and you’ll not only save fuel, you’ll also have happier, more comfortable passengers, not to mention less wear and tear on your vehicle.2. Where and when you drive can also have a huge effect. Conventional cars (hybrids and EVs are a different matter) are at their least fuel efficient in stop-start traffic.So, by avoiding peak-hour traffic, you can make a difference at the pump over time. Cars also use more fuel when their engines are cold, so making one longer journey with just one cold start rather than two or three short trips, each one with a cold start, will also save you fuel.3. If you do get stuck in traffic and it looks like you’ll be there a while, think about switching the engine off. An idling engine can easily use a litre per hour without moving you a single metre, and that’s terrible for fuel economy.This is also the reason there’s no gain to be had in letting a modern car warm up for five minutes in the driveway before you set off. You’re far better off driving away as soon as the engine is idling smoothly and getting some distance out of the fuel you’re burning.Just remember to take it easy until the engine has reached operating temperature. And then continue to take it easy in the name of fuel conservation.4. How your car is maintained can also make a big difference to fuel use. An engine that is tuned correctly will burn cleaner and use less fuel, and even details like a dirty air-filter can make the engine run less efficiently and will be picked up during a regular service.Don’t forget to have the whole car serviced, too, because dragging brakes or a poorly adjusted transmission can also add to fuel use.5. A lot of people never bother to check their tyre pressures, but these can make a bigger difference than you might think. Keep tyres inflated (for most cars) to around the 34psi mark (235 kPa) for a decent combination of ride quality and fuel economy.As well as saving fuel, your car will steer and brake better with 34psi in the tyres and the tyres themselves will last longer. Tyres can lose about 1psi per month just sitting around, so it’s a crucial regular check.6. Do you drive around with your air-conditioning running all the time? The air-con compressor causes drag on the engine which uses more fuel. In traffic and at urban speeds, you’re probably better off with the window open if it’s not too hot outside.That will flip at a certain road speed (depending on the aerodynamics of your car) and at higher speed, you might be better off running with the air-con on and the windows up to reduce aerodynamic drag (through the open window) that will cause the engine to work harder and burn more fuel.7. The same goes for roof-racks you’re not actually using at the moment. These contribute an enormous amount of aero drag and that means the engine works harder to pull it all through the air, especially at 110km/h.8. What’s in the boot of your car? If there’s a whole bunch of stuff you don’t need on a day-to-day basis (spare tyre, jack and tools aside) then leave it at home and reduce the weight you’re lugging around. A lighter car uses less fuel.There are no real trade secrets on how to get better fuel economy, neither does it matter if your car is powered by petrol, gas (LPG) or is a diesel engine.Nor does engine efficiency make any of these grass-roots measures redundant; even high-efficiency engines can be made to use less fuel.Clearly, buying a modern, high-tech car is the quick but expensive path on how to increase fuel efficiency, but stick with these tips and any car can go farther on less.

Q: What is braked towing capacity, and what does braked towing capacity mean in the real world?A: Braked towing capacity is the upper limit that your vehicle can tow without breaching safety, mechanical, legal or insurance boundaries.As the name suggests, it relies on the towed load (trailer, caravan, boat-trailer) having its own brakes so that the combination is not reliant solely on the tow-vehicle’s brakes to slow or stop.This figure is the absolute upper limit of what a particular make and model can legally tow.Braked vs unbraked towing is an important distinction as the limits for either are very different. Unbraked towing capacity which – again as the name suggests – is how heavy a load you can tow on a trailer without its own brakes (therefore relying on the towing vehicle for all slowing and stopping duties). It’s nearly always a lot lower than the braked limit.It’s important to understand braked towing capacity and not exceed it, for a variety of reasons, starting with staying within the law.If you exceed the towing vehicle’s braked towing limit, you’ll be unroadworthy and you could be fined even if there’s no incident.This also has insurance ramifications, and your insurer might walk away from you in the case of a crash involving a car that was towing too heavy a load.You’ll also void your car’s warranty by exceeding this limit as well as placing stresses and strains on the vehicle it was never designed to cope with. Brakes, clutches, tyres, transmissions and engines can all suffer from too much load on them.The crucial measurement in any assessment of braked towing limit is the mass of the trailer and whatever is loaded on it. This mass is what the police will measure if they think you’re over the limit. You can measure this mass yourself with a public weighbridge.Many councils now have weighbridges at recycling stations and, for a small fee, you can weigh your trailer either empty or loaded. By weighing the trailer empty, you’ll then have a reference number for how much you can load on to it before it exceeds the car’s towing limit.The other option is to use a set of towball scales that measure the amount of weight you’re putting on the car’s towbar, and there are now wireless, Bluetooth trailer scales that are placed under the wheels and the total mass added up for you.There are also plenty of online caravan weight calculator pages where you input all your known data and the website works out if your car is big enough for the job or whether you’re overloaded in any department.Just be sure to search for something like 'vehicle towing capacity calculator Australia' to ensure you find one that’s relevant to our local laws and limits.Terms you’ll find handy to know for this are Aggregate Trailer Mass (ATM) which is the total mass of the trailer when carrying the maximum load that the manufacturer recommends for that trailer or caravan.This is measured with the trailer disconnected from the towing vehicle and resting on its jockey wheel. This figure is determined by the trailer’s manufacturer and should never be exceeded.The other term you need to know is Gross Trailer Mass (GTM) which is the mass of the trailer when it’s hitched to your tow vehicle (and some of the mass is distributed through the tow-ball into the tow-car).Both these numbers are calculated by the trailer maker and are non-negotiable. There’s also a big difference between the allowable gross trailer weight braked and unbraked. That’s true of the tow-car, too, manufacturers have very different limits on towing not braked and with brakes.The empty trailer’s mass is what’s known as its tare mass. The difference between this number and the ATM for your trailer is the trailer’s payload capacity.At the moment in most Australian states and territories, there’s no simple, legal method of increasing a car’s towing capacity or a trailer’s loaded capacity.The trailer manufacturer will have their own method of how to measure capacity, just as carmakers have their own formulas for calculating maximum towing capacity.The towing vehicle’s braked towing limit, then, is not something you need to measure or calculate yourself. The number has already been determined by the vehicle’s manufacturer based on engineering and is not negotiable.You’ll find this info in the owner’s handbook. Neither is there an aftermarket package that can lift your braked towing limit. If you need to tow heavier loads, you need a bigger, heavier car that can do so. What is towing capacity in the handbook is the only number the authorities will be concerned with.Trailer brakes themselves come in two main forms. The simplest is the mechanical brake which uses the weight of the trailer to actuate the brakes via a mechanical or hydraulic link.As the tow-vehicle slows, the trailer tries to maintain its speed (basic physics at work) and the mechanical linkages are brought into play by the resulting force.Electric brakes are more complex but a more refined, sophisticated and efficient solution. The tow car is fitted with a sensor that, when it detects the brake pedal is pushed, sends an electrical signal back to the trailer which then applies the trailer’s brakes. You can fine-tune the amount of braking the trailer contributes on the run, making this a better system.To help put all this into context, here’s a quick run down of the typical braked and unbraked towing limits of popular types of vehicle:Dual-cab ute (Toyota HiLux 4X4): 3500kg braked, 750kg unbraked.4X4 wagon (Nissan Patrol): 3500kg braked, 750kg unbraked.Large SUV (Hyundai Palisade): 2200kg braked, 750kg unbrakedMedium SUV (Mazda CX5): 1800kg braked, 750kg unbrakedBe aware, however, that even within specific model ranges, details such as whether a vehicle is two- or four-wheel drive, and whether it’s petrol or diesel powered can also have an effect on those mandatory limits.Electric and hybrid cars often have much lower towing limits, too. So check each car out individually before making any decisions.

As we Australians take our fun more and more seriously, the idea of towing a caravan or boat behind our vehicles is an increasingly common one.This is (partly) what’s been driving the move to dual-cab utes as our big-selling cars of choice, as well as the increasing towing abilities of those cars.In the case of every new car and commercial vehicle for sale in Australia, the government dictates that it is rated for a maximum towing limit.That’s to ensure the vehicle remains safe to drive with a load attached, as well as hopefully ensuring the towed load won’t do any damage to the tow-vehicle.In the real world, it’s a lot more complicated than that, but it remains that towing more than your car is rated for is a sure way to wind up in legal trouble and, if the worst happens, an insurance swamp as well.So what is towing capacity in the first place? Towing ratings generally come in two forms: The unbraked trailer and the braked trailer.In the case of the former (and as the name suggests) the trailer does not have brakes of its own. For that reason, it relies on the brakes of the towing vehicle and, therefore, must be kept as light as possible.The braked-trailer limit, meanwhile, applies to trailers with their own electric or mechanical brakes that can contribute to the combination’s total braking force. With its own brakes, such a trailer can afford to be heavier.Either way, though, it’s illegal to haul a trailer and load of greater mass than the legal limit for a particular make and model.And get used to these terms: GVM, the total mass of the vehicle and everything in it (including the tow ball weight) and; GCM the total mass of the vehicle and trailer combination and everything in it/on it.Clearly, how much can I tow, is a very complex question. And, the info won’t be found on a compliance plate on the vehicle, either, you’ll need to look in the owner’s handbook for the details.But what if you need to tow more than that legal limit?Well, you could simply go out and buy a bigger, heavier vehicle with a higher towing rating. But what if you’ve already tipped plenty of time and money into making your current vehicle otherwise perfect for your tasks and lifestyle? Surely, an upgrade of that vehicle to tow a bigger load makes some sense.And that’s where the aftermarket comes in. As caravans, boats and worksite equipment gets bigger and heavier, more and more owners are turning to a towing upgrade to achieve their ends.The first thing to know is that the increasingly popular GVM upgrade is not the same as a towing limit upgrade. In fact, a GVM upgrade concerns only the payload of the vehicle and, if you then use that extra payload while the GCM remains the same, you might, ironically, have a reduced towing limit.So, does a GVM increase impact towing capacity at all? Not in a legal, upper limit sense, but such an upgrade is a way to increase towing performance and safety, if not actual capacity.Add a GVM upgrade to your, say, Ford Ranger, and it’ll still be legal to tow the same 3500kg, but it will do it more easily and more safely.GVM upgrades vary from vehicle to vehicle but often include components such as stiffer springs, revised bushes, stronger hitches, better dampers and wheel alignment adjustments.But even then, you might find you need bigger brakes, different tyres and even revised axles or wheel bearings to make the jump to a higher GVM.It all depends on the vehicle in question and there’s no one-size-fits-all GVM upgrade, so you need to have a specialist tackle your vehicle on a one-on-one basis with regard to how it’ll be loaded and how you plan to use it. The pros have a range of kits ready to suit popular fitments.The other thing to know is that you won’t be making 1000kg jumps in a GVM upgrade. Between about 300kg and 600kg is the gain you’ll make, but that’s a big enough difference for some to make the investment.But what about GCM upgrades? This is where it all gets a bit murky, because some specialists will tell you that since there’s no standardised test for a GCM upgrade, it can’t be done with any degree of certification.Other mobs will tell you they have GCM kits to upgrade a limited number of vehicles (typically the Toyota Land Cruiser and Prado stablemates) and that these can legally upgrade towing capacity.Because there’s no hard-and-fast government stance on this subject, the best we can do is give you what seems to be the current status quo on the matter:NSW, SA and Victoria will recognise a revised GCM if the vehicle has been independently inspected by a consulting engineer and usually the state’s own authorities.Tasmania allows a revised GCM if the kit has been previously certified by the manufacturer and professionally installed.Queensland no longer recognises a revised GCM above the GCM nominated by the vehicle’s manufacturer. That said, Queensland is said to be looking into this situation.WA, ACT and NT, meanwhile, do not allow a revised GCM above the manufacturer’s GCM if the vehicle is modified anytime after it’s been registered.Having said that, at least one major local suspension manufacturer we contacted insisted that “There is currently no process via a government body that will allow an increase of a vehicle’s GCM in Australia”.If you could legally increase your GCM, you’d theoretically also increase your towing capacity, again, provided you don’t gobble up the extra capacity by loading more into the tow-vehicle.But remember, that’s theoretically, not – as far as the law is concerned – practically.In the case of GVM upgrades, brand-new vehicles that undergo the upgrade prior to registration can be certified as safe and legal by the upgrade supplier.If you’re converting an existing car, you may – depending on state or territory – need to have an independent engineer sign off on the deal. The good conversion companies can usually put you in touch with these engineers.But don’t be put off by that requirement, as suspension upgrades for towing have been carried out for decades, so it’s familiar stuff for the right engineer.Again, a GVM won’t legally increase your towing capacity, but it can make a vehicle much better and safer at towing that same loads as an unmodified one.And GCM upgrades? You might want to make life simple for yourself and simply buy a bigger, heavier vehicle with a higher towing limit as standard. Many dual-cab ute, SUV and car owners are switching to a light truck for this reason.Even if you do just wish to improve your vehicle’s towing ability and safety (without a towing-limit increase) with a GVM upgrade, there can be traps. It’s far better to go to a specialist who has engineered a GVM solution rather than try to mix and match bits and pieces using guesswork.Air-bag helper-springs, for example, can be used quite effectively on some vehicles, but others (typically some dual-cab utes with leaf rear springs) can suffer catastrophic chassis failure through the use of air-bags.The same goes for changing spring rates. By mis-matching the front and rear suspension of a vehicle, you can easily wind up with a vehicle that is less capable and less safe as a tow-vehicle. This is not a project for the DIYer.

Towing capacity, as the name suggests is the maximum mass of a trailer and its load that can be legally towed on the road by a particular make and model.In Australia, there will usually be two towing limits listed for a car or ute, and those will be the braked and unbraked towing limit. The braked limit will usually be a lot higher than the unbraked limit, as a braked trailer contributes to the braking performance of the combination (the tow vehicle and the trailer).These days, many dual-cab utes are capable of legally towing 3500kg on a braked trailer, and that figure has become some kind of default setting for those buying tow-vehicles.This figure is much higher than in previous generations of cars and reflects the fact that cars are stronger and heavier than ever before (particularly the kinds of vehicles people choose to tow with) and that many vehicles have more powerful engines than ever before.Knowing your car’s towing limit is important because it means you can stay on the right side of the law when towing a load. Attempting to tow more than the manufacturer’s limit means you are technically unroadworthy.There are also insurance ramifications here should the worst happen and you’re involved in a crash. Even going beyond the towing limit off-road (say, on a farm) can mean that your car’s warranty will be affected.And beyond all those things is the fact that attempting to tow too heavy a load can easily damage your vehicle and will also make it unsafe in terms of its braking and handling.Unfortunately, the towing limit is a bit misleading as it’s not the only number you need to consider to stay legal and safe. The other important number is the vehicle’s GCM or Gross Combination Mass.This is the total weight of the car and its towed load, including all passengers, fuel and luggage on board.The catch is that some dual-cab utes (for example) might have a GCM of 5800kg and a towing limit of 3500kg, but once you hook that full amount to the tow-bar of the 2000kg ute, you discover that you have only 300kg of weight left for you, your passengers and your luggage. Exceeding the GCM is just as dangerous and illegal as exceeding the towing limit.The other trap for the unwary is exceeding the towball downweight limit. This is set by the manufacturer and is usually a maximum of 10 per cent of the total mass being trailered. Exceed this figure and you’ll be illegal and unroadworthy.The first consideration in choosing a tow vehicle is that it has the legal capacity to tow what you need to move. And that’s where the 3500kg thing has become a baseline number as it allows most people plenty of headroom.Beyond that, you need to choose a vehicle that will do everything else you’ll ask of it, as well as making the towing tasks as relaxed and safe as possible.While it’s true that many dual-cab utes have this theoretical 3.5-tonne towing ability, some definitely do it better than others. A turbo-diesel engine is a big plus (and petrol powerplants are almost history in this market segment, but they do crop up).Such an engine will give you the torque and flexibility you need, and it’s worth mentioning that some turbo-diesels are beefier than others.Some are okay up to about half that 3.5-tonne limit, but beyond they some of them can struggle, particularly on hills and in terms of their fuel consumption (not that fuel use is anywhere near the top of mind for most towing-rig owners).We’d also plump for an automatic transmission for towing. That is, a conventional automatic, not a dual-clutch or a CVT unit, as a traditional auto is simply stronger for longer when you use them hard.An auto makes manoeuvring easier and the auto gives a smoother take-up of the load and less wear and tear.The third consideration is the actual construction of the vehicle. While more modern, monocoque body designs can be lighter and handle better, for towing, the traditional body-on-frame construction is still hard to beat.The vast majority of dual-cab utes feature this, as do the big-hitters of the off-road wagon world such as the Nissan Patrol and Toyota's LandCruiser and Prado.Having established that it’s utes and four-wheel drives that are your best bet of a realistic 3500kg towing performance, what cars can tow 3500kg that we would recommend?It’s not a simple question, because there are plenty that theoretically can, including unlikely candidates such as the Bentley Bentayga and the Porsche Cayenne GTS and Turbo in wagon form. Clearly, we’re not talking tow-vehicles for the masses at that point.So let’s stick with the attainable tow-trucks.By far the best bet for the serious tower will be a dual-cab ute or off-road SUV. Those vehicles all tend to have the turbo-diesel engines, conventional automatic transmissions and ladder-chassis construction we were talking about.Beyond that, they also have all-wheel drive which can be a real holiday-saver in the case of a muddy campground or greasy boat-ramp.And why aren’t there any vans on this list? Because, when it comes to towing 3.5 tonne, vans of that capacity are not really available with most closer to 2000kg towing, or even less.Same goes for the SUV wagon versions of the dual-cab utes (Toyota Fortuner, Mitsubishi Pajero Sport and others). The switch form leaf to coil rear springs and an independent rear suspension system (for passenger comfort) means most of these lose a few hundred kilos of outright towing limit.That said, the Isuzu MU-X has a full 3.5kg limit as do V6 turbo-diesel versions of the newest Ford Everest.Neither have we listed the real big hitters, the US-market utes that have arrived here to cheers lately. Some of these have amazing towing capacities, but they’re too big and too expensive to be on the radar of most people.There are also plenty of other cars with 3.5-tonne towing capacity, but these ones below are the 3500kg towing capacity vehicles available for sensible money.A bit long in the tooth, the rugged old Toyota 70 Series is available as a ute or a wagon and also features the much-loved 4.5-litre V8 turbo-diesel. Impressive off-road, too. Priced from $69,000 (if you can find one).The Y62 Patrol bucks the trend by being a petrol-engined vehicle. But the V8 is smooth and powerful and tows beautifully. Another great off-roader into the bargain. Priced from $95,115.Known for their toughness and reliability, the Isuzu twins aren’t the last word in refinement or dynamics, but they are good tow-trucks. Full towing capacity restricted to 3.0-litre versions. Priced from: $36,200.The first choice in dual-cab utes for refinement and dynamics. Lots of options including cab-chassis, two and four-wheel-drive and all able to cope with 3.5 tonnes. V6 turbo-diesel dual-cab is the plum buy, but the Everest SUV is compelling, too. Priced from $35,930.Great reputation even if DPF woes have hurt that a little lately. Classic dual-cab, four-wheel drive ute layout is proof of concept. Four-wheel drive models carry the big 3.5-tonne towing limit. Priced from $40,155.All Defender models can tow 3500kg, including the 2.0-litre version. The bigger engined versions are best for the job, however. Not a cheap car any more, either. Priced from $82,960.The new off-roader everybody’s talking about, the Grenadier uses old-school packaging with BMW drivelines. Petrol or diesel will tow 3500kg. Priced from $85,500.The much anticipated new Cruiser gets a powerful driveline and superb off-roading ability. But it’s also a tow-master thanks to its sheer size and heft. Priced from $89,181.More upmarket variants of the Navara have a coil-spring rear-end which has been questioned by some who tow big loads. A process of continual improvement at Nissan has improved things. Huge spread of spec and prices. Priced from $32,300.By comparison with some of the Japanese makes, the South Korean Musso is a wallet-friendly way into 3500kg towing. Be aware, though, that engine performance in the Musso will be stretched at this limit. Priced from $34,990.

As a vehicle in its own right, there’s some evidence to suggest that the new Ford Ranger – especially in V6 turbo-diesel form - actually moves the dual-cab four-wheel-drive game along its evolutionary path.

Q: What is the difference between torque and power?A: It’s the age-old question that still baffles many car enthusiasts, but it’s really not that difficult when you break it down. As in: Torque is the force produced by (in cars and trucks) either burning a hydro-carbon fuel in an engine or (increasingly these days) applying an electric current to an electric motor. Power is simply that torque multiplied by engine speed.Fundamentally, then, an engine’s torque is the measure of its muscle and how much it can flex. Power is how fast it can flex it across a given period of time. In a boxer, torque would be how hard he or she could punch; power is how fast they could produce those blows.In the car world, the fundamental difference between horsepower and torque is that torque is real. Power, meantime, is the theoretical result of a mathematical equation that amounts to torque multiplied by revolution speed.Want to dig a little deeper? Okay, torque is a twisting (as opposed to linear) force that wants to rotate something. In the case of your car’s engine, that something is the crankshaft. It’s torque that actually makes the car move and accelerate (as that torque is passed from the crankshaft, though the transmission, differential and, finally, the axles).How fast it accelerates is down to power which, again, is a measure of how fast the engine can produce that torque-force moment. (The equation is also referred to as hp vs torque, horsepower vs torque and power vs torque, but it’s the same science.)Think of it a bit like a huge cargo ship. If you want to accelerate it through water, you need an engine that produces massive torque to get all that mass moving and keep it moving. It won’t be fast (relatively) but it will move thousands of tonnes through water which (in a macro sense) is quite sticky and produces a lot of drag. If, on the other hand, you want to go water-skiing, you use a smaller boat that doesn’t require the same force to get it moving, and power it with an engine that produces a lot of power that can move the vessel quickly.Torque vs power in cars is interesting, because it greatly affects the way the car feels to drive. A low-revving engine (like a turbo-diesel) with a lot of torque for its displacement, won’t rev like a petrol engine so it won’t make as much power (even though it can feel muscular because of its torque).The flip-side is a small capacity petrol engine which doesn’t make a whole lot of torque, but revs to 9000rpm, thereby multiplying that modest torque by a huge factor to arrive at a decent horsepower figure.The concepts of torque vs horsepower are no different between conventional petrol engines and electric motors. In both cases, the torque is generated at the crankshaft (or output shaft on a motor) and is then transferred to the wheels. In fact, the theory holds true for whatever power source we’re talking about. Even when you spin a lazy-susan on a table, you’re applying torque (from your arm) to do so. A wind generator? Yep, that wind hitting the blades of the turbine is creating a torque force, too.Actually, the windmill analogy is also a good way to explain how power is dependent on the rate at which that torque is applied. The faster that wind turbine turns, the more power (in this case electricity) it makes. It really is that simple.Getting back to cars, vehicles with lots of torque tend to be relaxed to drive and don’t require either you or the gearbox to work too hard. A car with less torque but lots of power, meantime (a typical arrangement for race-cars) will require more use of the gears to keep the engine spinning fast and producing plenty of horsepower.Where the engine develops its maximum torque also has an effect here. Again, smaller motors that like to rev do so because their torque peak is high in the rev range. That contrasts with an electric motor which can muster its maximum torque at standstill, which is why electric cars feel so frisky as you leave the green light.Having maximum torque at super-low revs is also why EVs don’t (generally) need more than one gear to take them through the whole range of everyday speeds. Contrast that with a 50cc Grand Prix motorcycle form the 1960s and 70s. Obviously, with just 50cc of capacity, these were never going to be torquey engines and what torque they did make was concentrated in a very narrow rev band. So, to keep the engine producing as much torque (and, therefore power) as possible for as much of the time as possible, the makers produced these bikes with no less than 14 gears. The riders were kept busy but amazingly, these tiny engines would propel the machine and rider to speeds of around 180km/h.

When a Ford six-cylinder engine earns a greater performance reputation than the V8s it sold alongside, and is also embraced by the aftermarket to the point where it’s being fitted to Holdens (not to mention everything in between) you know you’re looking at a landmark powerplant. And the engine in question is Ford’s in-line DOHC six-cylinder code-named Barra (short for Barramundi, a prized indigeno