TOP 6 ENGINEERING FAILS

By Evan Spence 9 Min Read

Factory 4X4s have a long history of getting things wrong, and since we’d need an encyclopaedia to cover them all, here’s the top six things that’ve been bugging us lately

Let’s be honest, most of us could find something wrong with our trucks without looking too hard. We’re not talking about that dent you collected last weekend when dropping down off that ledge or that driveshaft you booger-welded back together on the track that’s been making you feel like you’re driving during an earthquake; but from-the-factory problems that make you wonder if the engineer who came up with the idea got their degree out of a cereal box.

Advertisement

There’s no one make or model that’s more or less guilty than the others – they all do it. So let’s take a look at six of the most aggravating things you’ll find on many modern four-wheel drives.

 

EMISSIONS JUNK

Ok, I understand that things like diesel particulate filters (DPF) and exhaust gas recirculation (EGR) systems are necessary evils these days to keep manufacturers from falling foul of numerous government entities, but they are probably the cause of so many problems and failures that you’d swear they were designed by career politicians. Take EGRs for instance, which work by opening a valve to allow already burnt exhaust gasses back into your engine’s intake to be re-burnt in an effort to reduce emissions. And y’know what? It works… for a little while. The fundamental flaw is that by circulating ‘dirty’ gasses through the intake over and over again, carbon deposits will eventually build up and start clogging things, most notably in vehicles that don’t see many freeway kilometres. In other words it’s essentially engineered to fail, yet they’re a legal requirement. What the…!

 

TOYOTA TRACK WIDTH

Not to pick on Toyota here, but the late-model Toyota 70 Series has an inbuilt design feature that is lazy at best and downright dangerous at worst. There’s a lot to love about these things: time-proven suspension, inherent toughness aplenty and one of the best-suited engines to ever be bolted to a pair of chassis rails. So why on earth are they running a narrower rear diff than the front? Yeah yeah, the V8 wouldn’t fit without the front end being kicked out and the rear body is too narrow to accommodate a wider diff – I’ve heard all that. It’s still a gaping engineering flaw that should have been remedied at CAD stage. Why any car builder would introduce a potentially dangerous handling characteristic, particularly on a vehicle so well suited to towing and carting heavy weights, is beyond me.

Advertisement

 

WAIT, HOW MANY COMPUTERS?

You remember that old joke about the space-race, when the Americans spent millions of dollars developing a pen their astronauts could use in the vacuum of outer space, while the Russians simply used a pencil? I kind of feel that way about the abundance of computer-controlled electrickery in modern 4X4s.

No, I’m not suggesting we all go back to leaf springs, carbies and manually cranking windows, but when you need eight separate computers to operate the reclining mechanism on the seats I feel like we’ve crossed the line into technological overkill. It’s fast becoming “because we can” instead of “because we should”.

Worse still, computers are often mounted in places that are susceptible to damage off-road from dust and water – just look at the cause for most vehicle-on-a-tow-truck stories during big trips. More often than not it’s due to a faulty sensor or dust-filled control unit rather than mechanical failure.

Fuel injection, climate control and in-car entertainment are all great things, but the increasing reliance on electronics to be able to do just about anything (including drive) with our vehicles is a real worry.

Personally I blame the P38 Range Rover for starting the madness. Just ask anyone who’s owned one – there are more computers in those things than in a stealth bomber, and many modern four-wheel drives are trying their best to emulate it.

 

BIG TRUCK – LITTLE DRIVETRAIN

We’re seeing a trend towards four-wheel drives becoming bigger and heavier with each new model. Just take a look at the latest HiLux next to one of the original models to see what I mean. However, despite adding higher output engines and more sheet metal than ever, manufacturers still insist on running transmissions, diffs and axles that are better suited to a vehicle with half the power and pant-size. And once owners add bar work, winches, bigger rubber and a week’s worth of camping gear the problem only gets worse. That they don’t over-engineer these common weak points from the get-go makes it hard to trust their decision making capabilities, doesn’t it? Nissan is one manufacturer who got it right, bolting massive diffs and transmissions that weigh more than a Sierra underneath the Patrols, and then they go and put it all behind the ZD30…

Advertisement

 

STEERING ARMS – YOU’RE JOKING, RIGHT?

Due to the design of most mechanical steering set-ups, the tie-rod(s) and draglink are right out in front of the axle. This means that if you’re going to impact a rock off-road, it’s often the arms which are the first point of contact. Now common sense would dictate that you’d build these things pretty stout right? I mean, we routinely push our 4X4s over unforgiving terrain, yet the factory saw fit to bolt on a drinking straw to operate one of the most important parts of the entire vehicle. How do these people stay in a job?

 

DIY SERVICING? FORGET IT!

This one grinds my gears in a big way. Manufacturers are willfully making it harder to service your vehicle at home. Most new 4X4s don’t even come with a dipstick for the transmission, and a couple have even stopped putting them on the engine! Then there’s the exaggerated service intervals they keep telling us about – I don’t know about you, but I’d reckon there’s a big difference in driving 20,000km through the Outback towing the camper as opposed to doing 20,000km of commuting to work and dropping the kids off at soccer practice. Not to mention I’d rather do my own servicing so I know exactly what fluids and filters have gone into my vehicle, and it gives me a chance to run my eyes over things like driveshafts, ball joints and mechanical linkages and make sure everything’s ship shape – probably a bit more thorough than the first-year apprentice who’d be doing it at the local workshop.

Don’t get me wrong, there’s a lot to be said for dropping your rig off at a shop and picking it up a couple of hours later running like a champ, but taking the choice away from those of us who enjoy doing the work ourselves is just stupid.

Words by Dex Fulton


Share This Article
Leave a comment