The Evolution of the Modern Tow Vehicle

Dan Everett — 16 August 2017

“They don’t build them like they used to.” It’s a phrase you get used to hearing when you drive an old 4WD, and one that I agree with every time I hear it — but not in the way they meant it. It’s almost become the theme song each time I’d swing open the thick steel door with chrome trim on my 30-year-old 'Cruiser. Of course, it’s complete with all the mod cons of the '80s like leaf springs and drum brakes, even a good old-fashioned carburettor under the bonnet. 

I mean, how could you go past all the amazing features of a classic rig? For starters, there’s the solid steering column that promised to keep me pinned in the driver’s seat in even a mild accident. The safety brakes that meant no matter how hard I mashed the pedal there was never any risk of stopping too quickly. And who can forget the safety break-downs constantly keeping me in the driveway instead of out there on the dangerous road. 

Yep, they sure don’t make them like they used to, and it’s a bloody good thing, too. Y’see as much as it’s easy to romanticise old 4WDs for their rugged simplicity the reality is they’re just not as good as modern ones in any way imaginable. New vehicles are more capable, more comfortable, safer in just about every situation and will chew less fuel to boot. They’re the perfect partner for anyone serious about spending their weekends out on the tracks and not in the driveway spinning spanners, but are constantly seen as a soft option. Normally by a hairy-chested man adjusting his points, while you’re three hours up the road at camp already. 



We figured it was high-time we pointed our lab-designed LED spotlights at modern 4WDs to see just how much better they’re making life on the tracks and opening up whole swaths of Australia to everyday Aussies.  

THE WAY THINGS WERE

For some reason offroaders have always been resistant to change, even though change was happening long before there was offroading to apply it to. While we’re busy tut-tutting over high-tech diesel engines the very first 4WD was an all-electric endurance racer designed by an enthusiastic 18yo unqualified engineer in the dark corner of a coach builder’s workshop in Vienna in the late 1800s. 

The then young Ferdinand Porsche (yes, that Porsche) was experimenting with an electric motor in wheel design that captured the world’s attention when it rolled out into the spotlight. It culminated in the beast known as La Toujours Contente (French for always content), a monster of a car with over a tonne of its 1500kg weight being taken up by the batteries and motors alone. 

The design was eventually refined into the Porsche Semper Vivus (Latin for always alive) where twin 1.2L petrol engines powered twin electric motors in the front wheels. The system was that advanced it’s still recognisable in modern hybrids with NASA even studying the original all-electric models for its Lunar Rover program. 

We’ve got a technological past in the 4WD community and are only just starting to accept it again.  

OFFROAD PERFORMANCE

Alright, let’s kick things off right where the biggest criticism of modern 4WDs falls — offroad ability. The general consensus is older 4WDs are more capable than their younger siblings but it’s missing out on a few key factors that make a whole world of difference.

There are two benefits to solid axles. Strength through simplicity, and articulation due to design. But both of those are in a perfect world. In execution, most solid axles require significant upgrades to handle the loads seen in serious offroading or heavy towing. There’s a reason so many aftermarket companies offer bracing kits, solid pinion spacers and heavier duty gears; And with stiff load-carrying suspension they generally lack on the articulation front too. The quick and easy answer to limited articulation is to fit a couple of diff locks, as long as you’ve got a tyre with grip you’ve got forward momentum. Sounds great in theory until you consider the fact that most modern 4WDs come with a diff lock or two as standard anyway,  quickly levelling the playing field. A properly built modern independent 4WD can address strength issues in similar ways to old buses too with flat CV joints and regular maintenance sorting most issues.

Now let’s take a look at the dark horse ­— technology. Older rigs had very rudimentary 4WD systems. The brakes were the brakes, the driveline was the driveline. There wasn’t much else to it. Modern 4WDs on the other hand use an array of sensors and computer programming making themselves incredibly capable. The big one is traction control. Older systems would simply cut power if they sensed a wheel spinning, new systems will sense which wheel is spinning and apply the brakes to that wheel alone helping send drive to the opposite wheel. It acts like a pseudo diff lock with far more versatility. The Jeep Grand Cherokee takes things one step further with a centre diff using the system to send up to 100 per cent of drive to the one wheel with grip if the other three are spinning uselessly, and that’s something a traditional diff lock can’t do. 

Four-wheel drive modes have also become common in recent years with vague names like mud or snow, but how they actually work is more proof how intelligent 4WDs have become. Depending on the mode you select, the vehicle will change all sorts of parameters to make it more capable in the terrain you’re driving in. They change shift points in the automatic transmission either higher or lower depending on what’s needed ­— they can knock sensitivity out of the throttle if you’re in rocky terrain allowing you to send more constant drive to the ground or bump it up in sand giving you more response. If the vehicle is fitted with adjustable suspension they can also automatically adjust ride height to either give more clearance if required or lower down for improved comfort and fuel efficiency.

TOWING POWER

The 1HD-T, Toyota’s holy grail of old-school mechanically injected turbodiesel six’s was a huge 4.2L six-cylinder that weighed as much as a softfloor camper and powered everything from fully loaded Cruiser’s right through to buses. It made 361Nm of torque. The new 2.8L 4-cylinder in the HiLux? It makes 450Nm. See where I’m going with this?

When it comes to pure towing grunt, modern engines make their older brothers look downright sluggish in comparison. Sure, you need to run cleaner fuel and keep them serviced regularly, but treat them right and you’re paid back with huge amounts of power and driveability that makes lugging campers around the countryside a more enjoyable experience. 

In older engines, power improvements like that could almost always be chalked up to running higher compression pushing the engine to its limits. These days they’re getting the power and torque gains by chasing efficiencies rather than brute force. 

The big boon has been common-rail diesel technology. Older mechanical diesels were clumsy systems where the injection pumped controlled everything from timing to fuel injection to fuel pressure. The fuel went in when it went in and that’s the end of that. Common rail systems use the pump to prime a high-pressure fuel rail that then has individual electronic injectors all controlled directly by the computer. The results are far more precise control over the combustion cycle resulting in twice the torque output per litre of engine capacity and significantly less fuel consumption in the process. The whole system is backed up with more intelligent six or even eight speed automatics that can juggle the engine’s RPM to have it making power when you need it and sipping frugally when you don’t.

KEEPING YOU ON THE TRACKS

Over the years I’ve had the keys for everything from a 1970 Corolla through to a $250k Land Rover, and been through around 40 personal cars with a similar (albeit much cheaper) range. I’ve crossed a continent in a 30yo van complete with shag-pile carpet and drifted sideways in twin-turbo Mercedes 4WDs and the one constant has always been this: The older the car, the less reliable. It’s an unpopular opinion but one that’s proved true time and time again, just ask me about stripping the interior to replace a heater hose at 3am in Death Valley. 

The reality is while older 4WDs might be simpler, theoretically making them easier to repair, they’re also far more likely to need a knowledgeable set of hands under the bonnet. In a perfect world you’d be a diesel mechanic and travel with your full workshop with you ready to take on any repair, but in the real world unless the issue is something simple you’ll be calling for a tow-truck to get home anyway.

Modern 4WDs on the other hand are far more complex meaning field repairs are almost impossible, but the chances of them stopping is significantly less. Sure, it’s not the manly answer, but in most cases you can replace your tool rolls with a satellite phone and spend your time enjoying the journey rather than playing bush mechanic. 

Staying on the tracks means more than reliability too. Modern 4WDs are far better at keeping you in one piece in an accident, and avoiding accidents all together. We’ll use the Ford Ranger as an example as it’s one of the most technologically advanced 4WDs until you step up into the big dollar stuff. It uses an array of sensors to work out exactly what’s going on with the tow-tug and respond accordingly. If you’re about to run up the backside of a slow-moving caravan while you stare off at the sunset it’ll beep and flash at you while it pre-loads the pedal then begins braking for you. If you then swerve and it detects a roll-over is likely it can tactically cut and re-apply engine power and brake individual wheels to keep you shiny side up and it does it all without you realising.

Each make and model has its own safety systems and some we haven’t mentioned here, but it should be clear by now that modern 4WDs have incredibly capable technology making spending long days on the road far safer.

TOURING RANGE

When we talk touring range, people often bring up long-range tanks like the only thing stopping them from pushing on is the distance between drinks. The reality is the driver is almost always the weak link in the system. Even the roughest 4WD will be more than happy to keep driving long after you’re begging for a rest. 

Sure, modern 4WDs with lower fuel consumption can have a longer fuel range than less fuel-efficient vehicles, but the real benefit is how much they isolate you. Let me explain. I’ve done the Old Tele Track in Cape York twice in the last couple of years. Once was in a ’93 LandCruiser, petrol powered that needed the dizzy dried out after every crossing. It also had no AC so windows down. The second time was in a brand new D-MAX. Despite the Cruiser being touted as the more suitable vehicle I was a hot mess at the end of each day. Dirty, hot, rattled to pieces from the corrugations, and hands burnt to bits from playing mechanic every 20 minutes. Comparatively the D-MAX was like riding a magic carpet. I’m still not sure what the engine looks like, but I know that I was a cool 21C the whole time, with a softer ride, less engine drone in my ears and wasn’t drinking water at anywhere near the rate I was in the Cruiser. By being a physically nicer place to be the D-MAX meant I could spend longer in the hot-seat each day. I didn’t mind pushing on to that better campsite, was happy to spend longer sitting by the river or having a yarn in a roadhouse and could call it a night where I wanted to, not where I had to. 

It's not just offroad where things are improved either. Modern 4WDs have a whole host of gear all designed to make the long haul physically less taxing on your body. Things like smoother automatic transmissions, more power to overtake, and adaptive cruise control all team up to make long-distance days on the blacktop an opportunity to go exploring where you want rather than fighting the tow-tug to make it do what you want. Make no mistake, if you’re currently on the road in an old 4WD a modern one will see you travelling further each day and doing it easier. 

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towing tow vehicle 4wd technology