Articles by David Morley

When a hybrid’s batteries are flat,  the petrol engine starts up and continues to drive the vehicle while also offering up some charge to the flat battery. Fair enough, and that’s precisely how most hybrids work.

Take it as read that the hydrogen fuel cell is coming to a car park near you. While battery EVs and hybrids are the current new-tech go-tos, it won’t be long before a fuel cell-powered car or SUV could be in your future.

While electric vehicles (EVs) are covered in the various state and territory motoring clubs’ roadside assistance packages, the reality is an EV that has run out of charge in most parts of Australia will be rescued on a tow-truck, rather than recharged by the side of the road.

A modern EV won’t just suddenly stop in the middle of the road if it runs out of charge. While it’s tempting to think than an electric car flat battery is the same as an empty fuel tank in a conventional car, an EV is actually a bit smarter than that.

The simplest advice is to not push your luck and either fill up before the low-fuel warning light illuminates or as soon as possible after it does. Trying to guess how far you have left to go before running completely dry is asking for trouble.

Looking at a single fuel consumption figure might give you part of the picture, but a set of average consumption figures covering different cars is a great basis on which to make a comparison.

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.