While we love our solid axle four-wheel drives, IFS is here to stay and has taken over the new 4×4 space.
For some, this is a hard to swallow pill. But, IFS (independent front suspension) is simply better for touring than a solid front axle. It has better ride quality; better handling; better tuneability – the grass really is greener on the old double-A-arm side of the fence, folks. This is coming from somebody with two solid-front-end rigs too. Every time I jump behind the seat of an IFS tourer I’m reminded how much nicer they are at eating up the highway miles, dirt road horizon-chasing or belting over endless soft sand dunes.
We’re not telling you to go out and trade in your 79 for a HiLux. But if you’re planning a build for some long-distance remote wheeling, we’d pick an IFS vehicle nine times out of ten.
Let me explain why. A decade or two back you’d had to have had rocks in your head to go with IFS over a tried-and-true solid axle under the front, but over the last couple dozen years, the aftermarket has basically solved all of the shortcomings of independent suspension so there’s next to no reason not to choose it really.
Sure, if you’re building a dedicated rock crawler there are some good arguments for staying with solid axles. But for pretty much everything else a hard-mounted diff at the pointy end is really a better option.
Still, there is a bunch of bad information kicking around. So we thought we’d do a quick rundown on the parts you’re going to need if touring in your IFS four-wheel drive is on the cards.
IFS Struts
Struts, coilovers, shocks and coils. Whatever you want to call them, are basically a coil spring and shock absorber rolled into a single unit (which we’ll refer to as struts from here on out) and are the bouncy bits of choice for the majority of four-wheel drives these days.
From the factory, most struts are not built to handle the weights of things like barwork and winches. Nor are they really designed to take hitting a washout on the road out to Mount Dare at speed without some sort of explosive failure.
A well-built aftermarket unit is an absolute must. Don’t be tempted to go for the cheapest candidate either. Quality suspension will pay for itself many times over throughout its life so it’s well worth spending a bit extra here. In general, you’re chasing about 2-3in (50-75mm) of lift from your struts. But be aware that the higher you go, the higher the stresses that are placed on joints and angles of operation, so further mods may be required.
IFS Upper Control Arms
Lifting your front end can lead to a few issues with your stock upper control arms (UCAs). The ball joint closest to the wheel can be placed in a position that will see it exceeding its designed angle of operation – in other words, it’ll flog out. Quickly.
Standard double-A-arm set-ups also have a designed-in amount of camber change through the arc of travel (as the wheel moves up and down). So a taller ride height can adversely affect your camber settings at both ride height and as the suspension articulates.
The solution? Easy. Grab a set of built-for-purpose aftermarket UCAs. Be sure to choose a set that has a high-quality ball joint that is heavy-duty and designed to handle the rigours of off-road driving (spoiler alert: in general, the factory ones cannot).
If you really want the bees knees of UCAs, grab yourself something like these Superior Engineering billet upper control arms with uprated ball joints. They offer integrated coil clearance, HD ball joint and poly bushes at the chassis end with full tweakability of your camber and castor settings.
IFS Lower Control Arms
In general, most lower control arms from the factory are not too bad really. There are always exceptions, but for most people’s needs, changing them out is not often required. Aftermarket bush replacements are common to enable a higher degree of adjustability. But again, most of the desired results can be achieved through aftermarket UCAs.
Now, if you’re going for a full desert race-truck then a custom set of upper and lower arms is a must. But we’re just talking about some Outback touring in this article, so take it easy, BJ Baldwin.
Diff Drops
When your front suspension is lifted with a taller set of struts, your wheel mounting surface (WMS) is essentially moved lower compared to your differential. This causes the angles your CVs are working on to increase, which can dramatically shorten their time on this world.
In an ideal world, your CV halfshafts will be working on as close to flat angle as possible. But due to the wheels moving up and down as the suspension articulates, this is rarely the case. Now, all CV joints have a safe working angle – the larger the amount of height separation of the diff compared to the WMS, the more severe that angle becomes. This is where a diff drop comes in.
It effectively lowers your diff away from the chassis. Lessening the CV angle, keeping them happier and much longer living. This is generally only for larger lifts. But it’s worth being aware of if you think trackside CV changes suck. Because you’re right. They do.
Coil Conversions
No complete suspension system will ever focus on just one end of the vehicle. If you’ve just spent all this time and effort getting your front end dialled, it makes sense to get things working out the back too. Most dual-cab utes will have leaf-springs for load-carrying capability. But again, it ain’t 1990 anymore McFly. We’re in the future and there are a few kits on the market, like these, again from Superior Engineering, available to convert your leaf rear end to coils and get it happy carrying the loads you want for touring as well as flexing like a champ.
A full coil conversion is not for everybody, however. There can be a great many gains from changing out your leaf-packs for high-quality aftermarket ones, bolting in some proper shocks or even fitting up a set of bags for those times when a little extra load-carrying is required.
No matter what you’re after, it’s all possible. What a time to be a four-wheel driver.
Underbody Protection & Chassis Bracing
Ok, so it’s not really part of the suspension exactly. It is part of a solid touring set-up, though. We’re talking about underbody protection. It’s probably the cheapest insurance you can buy for your four-wheel drive. Sumps, gearboxes, transfer cases and fuel tanks all tend to hang pretty low on most rigs. You’d be amazed how easy it is to drag one of them over a rock or across a deeper-than-expected rutted out track. Potentially causing thousands in damage and bringing your trip to a sadface halt.
A good bashplate or two can stop this from happening and keep your undercarriage in better condition than an Olympian.
Oh, and while we’re talking non-suspension items that are still important. If you’re carting heavy loads in your canopy or are towing large trailers, look into having a chassis brace kit installed. We’ve all seen those pics online of folded-up utes, and according to Mark Twain (probably), it’s always a good life rule to avoid inadvertently becoming an internet meme. Big loads and rough roads? Strengthen your chassis as well as your suspension.
