Straight out of the box, the 79s are still one of the best options for heavy duty towing and off-road use on the market. As many of us have found out, however, the stock suspension set-up leaves a lot to be desired. Especially when we're loaded up or are looking to tackle more difficult tracks safely. It's not that the stock springs and shocks are bad exactly, it's more that they're not really suited to how these vehicles often get used.
Why the 79 Series Needs More Than a Stock Setup
The main issue is that the limits of the stock set-up are quickly reached and exceeded. If you're towing the tinny down the ramp on the weekend or using the Cruiser for light-to-medium-duty off-roading, then the factory suspension is more than capable of handling it. But most of us buy these rigs to haul the tools during the week and tow large caravans or boats when we've clocked off.
Not to mention carry a family's worth of camping gear on the tray while tackling the harder tracks and remaining drivable on-road without sacrificing comfort or capability on remote trips. It's a lot to ask of any suspension, particularly the rear leaf springs.
Ultimately, there's a significant gap between what the 79 Series is engineered for and what tourers actually do with it.
What a Touring Build Does for Your 79 Series
There are hundreds of suspension products on the market for the 79, and many of them work well, but rather than taking the scatter-gun approach to building your suspension you're much better off with a little prior planning. The trap so many fall into is not accounting for the cumulative increase in weight with accessories and the subsequent reduction in available payload. The more accessories, the greater the mass the suspension has to support, the higher the leverage being placed on it, accelerating wear and tear. On top of that, it's all too easy to eat into your GVM to the point where you can barely carry a conversation, let alone an RTT or a couple of dirtbikes.
The absolute first thing any 79 owner should do to avoid this is calculate exactly what they're looking to tow and carry. Then work out what's going to live on the vehicle full-time (canopy, drawers, fridge etc.) and what's going to get added when it's time to pack up for a trip (recovery gear, camping accessories, dirtbikes, trailers etc.).
Finally, determining what sort of driving you're building the vehicle for must be considered. Towing the caravan to paid sites and general touring duties will need a different suspension system to a rig that's planning on doing the hardcore tracks and travelling relatively light.
With a solid plan in place, it makes choosing the correct suspension for your needs a much more straightforward process.
Your First Decision: Leaf Spring Upgrade or Coil Conversion?
The type of springs you run in the rear will play a big part in how your vehicle performs at its designated tasks.
Staying Leaf Sprung
Leaf springs are progressively rated in nature (the more weight you add the stiffer they become) and are designed to take heavy loads. They're also the cheaper option over a full coil replacement. They do offer some compromises in comfort, flex and can be more difficult to dial in the spring rate exactly to your chosen loads, but this can also be an advantage for some people.
Overall, leaf springs are still a solid option for heavy loads, but coil conversions offer huge advantages. They can be tuned for load carrying while offering more comfort, more flex and more adaptability if the load over the rear end is regularly changing.
Coil Conversions
A coil conversion offers numerous advantages. The first is a smoother more controlled ride, particularly over corrugations and uneven terrain. They also offer much improved wheel articulation while improving handling and load carrying.
Properly done, a coil conversion will also reduce strain on the chassis compared to a bolt-on set-up. Once installed, there are literally no downsides.
They can be fully engineered for street legality and keeping your insurance valid, and can be dialled in to suit the loads you're carrying or towing perfectly. You can add your preferred shocks, tune the travel to suit the type of driving you like to do, reduce fatigue over long trips and generally just significantly enhance the overall driveability of your 79.
They can also be installed in conjunction with a GVM upgrade, offering the best of all worlds.
How Much Lift Does a 79 Series Need?
What are you really using your 79 for? It's the question that will likely determine the amount of lift to go with.
2 Inch Lift
While a 2in lift is considered entry-level by a lot of people, there are plenty of good reasons why it's the most popular lift on the market. It will give you a useable amount of clearance and articulation without unduly affecting handling or blacktop performance, allow a decent upgrade in tyre size and you can dial them in to suit a wide range of loads. They also do not generally require certification and are perfect for daily driving or light touring use.
3 to 4 Inch Lift
While things start getting a little more complex with 3-4in lifts, so too do the advantages. Yes, you need to factor in the extra cost of castor correction and replacement radius arms, not to mention the certification to maintain road-legality, but with a proper and comprehensive kit it opens up a huge range of possibilities.
Everything from tyre size, load selection, wheel travel and ride comfort in any permutation you want are all available in this lift range, it just comes down to what you want. Contrary to popular belief, handling can actually be improved at these ride heights with the correct kit and installation, but there are compromises.
Especially if running larger rubber. Fuel usage and centre of gravity both go up, but most people think the trade-off is worth the advantages when off-road and touring.
Does Your 79 Series Need a GVM Upgrade?
A well-kitted touring build will come very close to consuming the payload budget available for the 79s. The pre-22 GVM of 3300kg and the post-22 GVM of 3510kg may sound like a lot, but some bar work, tyres, a canopy, drawers and extra fuel and water tanks will have you perilously close to the limit. Add a couple of passengers, a fully-loaded fridge and a couple hundred kilos of tow-ball weight and you're likely going to be driving illegally.
Say goodbye to your insurance and say hello to serious legal consequences should the worst happen.
With a GVM upgrade to 3900kg or 4200kg (depending on the kit) you're giving yourself a lot more breathing room and making sure your hard-earned goes towards fuel and adventure rather than trying to recoup a significant loss. This is not a mod everyone needs, but if you're towing or carrying heavy loads it's well worth investigating if it's for you.
Choosing the Right Shocks for a 79 Series
Shocks are often seen as a bit of an afterthought, but they're an integral part of the suspension and must be matched to a set of springs. The rate of the springs and the valving of the shocks can have a huge impact on the system working harmoniously or trying to fight itself through the range of travel. Your shocks will have the most effect on ride quality and can be a direct influence on available articulation, so they're important to get right.
The main options are twin-tube, monotube and remote reservoir. Twin tube offers great durability for lighter-duty rigs and are a fantastic entry level shock absorber. Monotube generally offer a step up in quality and range of sizes. Some high-end examples can be re-valved to suit your vehicle's loads perfectly. Remote reservoir units offer the most resistance against heat build-up (shock fade) and are arguably the best of the three for heavy-duty builds.
Shocks are a whole subject on their own, so if you're looking for information on your specific build, get in touch with the team and we can help you make the right choice.
79 Series Upgrades Worth Knowing About
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Radius Arms - A must have for any comprehensive front coil suspension, particularly for larger lifts. They optimise suspension geometry and can significantly improve ride comfort and wheel articulation.
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Castor Correction - As front suspension is lifted it significantly loses castor angle, which has a direct effect on steering, making it become vague and prone to vibration. By correcting the castor angle after a lift you're maintaining your handling and driving comfort.
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Steering Dampers - These smooth out the jarring and vibrations encountered through the wheel when driving off-road or over corrugations. A quality damper can make a huge difference to driveability after a lift.
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Adjustable Drag Links & Tie Rods - The steering arms on your front diff play an integral role in minimising bump-steer and vague handling. By adding in adjustability to the arm lengths you can dial in the perfect length for your vehicle and lift.
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Chassis Bracing - With a heavy-duty build the stock chassis is prone to bending or forming cracks. With some purpose-designed weld-in bracing you're not only better able to support heavy weights, you're also future-proofing your rig.
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Speed Correction - Larger tyres throw your speedo calibration off. By adding in corrective measures you're fool-proofing your ride and preventing your speedo from inadvertently lying to you.
79 Series Suspension FAQs
What is the factory GVM of the LandCruiser 79 Series?
Either 3300kg pre-2022 or 3510kg post-2022. Both can be upgraded to 3900kg or 4200kg depending on the GVM upgrade kit you choose.
Do I need a GVM upgrade if I'm not towing?
It depends. If you're fitting multiple accessories like a heavy canopy, large tanks, drawers, a serious battery system and a large awning and rooftop tent then a GVM upgrade may well be required.
Can I run a coil conversion and keep my GVM upgrade?
Yes, absolutely. Many GVM upgrades can come with a coil conversion as part of the kit. It's always best to discuss your needs with the team before making any concrete decisions though.
How much lift can I run without engineering in Victoria?
The total allowable lift is 75mm over standard in Vic. 50mm of that can come from the suspension and 25mm from the tyres. After that, engineering must be factored in.
What's the difference between the Outback Tourer and VSB14 kits?
The Outback Tourer is a Pre-Registration GVM Upgrade, allowing it to be registered with the increased GVM from new under the Second Stage Manufacture (SSM) scheme. This is generally the most straightforward option, as the increased GVM is recognised nationally as part of the vehicle's original registration record. The VSB14 kits are a Post-Registration GVM Upgrade, completed after the vehicle has been registered, and must be certified under the applicable state or territory modification requirements to legally increase the vehicle's GVM. While it provides a legal increase in GVM when certified, approval and transfer requirements can vary between states and territories.
Build Your 79 Series the Right Way
