Slide on Campers: Do I need a 4WD Suspension Upgrade?

So maybe you’ve noticed that Trayon offer one of the lightest, if not the lightest, slide on camper in its class?

After looking around at the slide on camper range, you may ask “do I still need to upgrade my vehicle’s 4WD suspension?”

Do I Need A 4wd Suspension Upgrade

We Get Asked This Question Quite a Bit

Many other slide on manufacturers start with a dry weight well above 600, 700 even 800 kg+. This leaves little to no room for gear within the maximum load carrying capacity (people, gear, fuel, water etc.) of most Australian utes (which is commonly around one tonne). Going over your vehicle’s load carrying limits can have serious consequences for insurance, warranty and the law. Not to mention the huge safety risk. This makes a 4WD suspension upgrade an absolute must!

Trayon campers are built specifically to be well within your vehicle's unmodified load carrying limits. Trayon’s class 2 slide on camper dry weight starts at 390 kg. When fully loaded with everything you need for a full swing off road adventure, it can push up to 700 kg quickly (depending on the load you choose to add of course).

That's well within the one tonne carrying capacity of many Australian utes.

So since it is within safe load carrying limits, why would you still need a 4WD suspension upgrade?

Well, here’s the answer.

Why Would I Still Need to Upgrade My Vehicle’s 4WD Suspension?

If the question is solely about the ability of the vehicle to handle the weight of a Trayon, then “no, generally you don’t need to upgrade 4WD suspension to carry the weight, so long as the slide on camper is loaded properly.” This means the majority of the weight is above or in front of the rear axle (food, water, gear).

But wait, there's more to it than that! You’re asking the right question, but for the wrong reasons.

The team at Trayon regularly get this question from their customers. With over 24 years experience learning the ins’ and outs’ of camping in the Australian outback with slide on campers, we have an answer for you that has been tested and proven time and time again!

First, let’s start by asking a few questions that identify the foundation of your off roading adventure.

Where Do You Want to Go and Will You Be Going Off Road?

Naturally, we get a variety of responses this question. But the key thing we notice across responses, is that everyone seems to have a slightly different view of what ‘off road’ means.

What Do WE Mean By ‘Off Road’?

When we refer to ‘off road’, ‘off the beaten track’ or ‘in the Outback’, we mean anything that is off the bitumen.

You don’t have to be hanging three wheels over the edge of a cliff or shooting down Gun Shot Creek up at Cape York Peninsula!

It could be plain gravel, sand, mud, rocks….that's all off road! Basically, anytime you leave the bitumen you are going ‘off road’, and increase the stress and risk placed on your vehicle. So it’s more about your intention to leave the bitumen and the terrains you wish to cover, than it is about the slide on campers weight.

That's what really drives the need to consider a 4WD suspension upgrade.

trayon camper slide on camper 4wd suspension Off road

Let's Remove Second Hand Vehicles From the Discussion

When explaining our 4WD suspension advice to customers, we like to do it from the perspective of a new vehicle. You can apply this advice to your older vehicle, but a second hand vehicle comes with a whole bag of other considerations to do with age, wear and tear, which we won't discuss in this post.

For example, perhaps the second hand vehicle has been carting one tonne of firewood or trade tools on the same springs for the last 10 years.

The 4WD suspension on that vehicle is almost definitely spent, and will probably need a whole new set up underneath. That’s leaves, coils, shock absorbers; everything probably needs to be replaced.

So let’s start at the top from the perspective of preparing a brand new vehicle for the purpose of going ‘off road’.

Our Key 4WD Suspension Advice

If you plan on going off road, that is leaving the bitumen with or without a slide on camper, you will require 4WD suspension work.

What's the 4WD Suspension Benchmark For the Outback?

We realise there’s an overwhelming amount of potential 4WD suspension upgrades available. For example 4WD shock absorbers, coil springs, sway bars, torsion bars, leaf springs, 4WD suspension lift kits, and airbags to name a few.

We also realise that each private off roading enthusiast you talk to will have a different idea on the best 4WD suspension setup. And the salesman you’re asking are probably giving you a whole different story altogether!

First and foremost, to tackle the Outback with a slide on camper you should be aiming for constant load suspension.

Some Trayon customers do intend on keeping almost entirely to the bitumen. In these cases, some good quality 4WD shock absorbers should do the job to keep you steady for your nomadic road wondering needs.

But in off road situations whilst carrying a load or towing a trailer, constant load suspension is the benchmark.

trayon camper slide on camper 4wd suspension by ant hill

What is Constant Load 4WD Suspension?

Constant load 4WD suspension is made to carry a constant load of extra weight at a certain height. Constant load springs vary in the amount of constant weight they can carry, and usually come in the following weight ratings:

  • 0-300 kg
  • constant 300 kg; or
  • constant 600 kg.

For example, a constant load spring rated at 600 kg will keep the vehicle two inches above its standard height when loaded up.

Standard springs in the same situation will sag, as they aren’t designed to handle that constant load. Eventually, something has to give. And you really don’t want to be 500 kilometres from the nearest mechanic when that happens!

The vast majority of mid-range four wheel drives rolling off the showroom floor (e.g. Nissan Navaras, Mitsubishi Tritons, Toyota Hilux’s, Ford Rangers etc.) don’t come with constant load 4WD suspension.

Most car dealers will tell you that these vehicles are one tonne utes (or close too). What they don’t explain is that when a vehicle doesn't come with constant load 4WD suspension, the springs will sag and the weight will actually be carried on the suspension bump-stops! This can happen regardless of whether your carrying 100 kg of cement for home renovations or a 650 kg fully loaded slide on camper for your weekend camping trip.

When under constant load, your stock standard suspension will most likely sag to various extents.

Why Do You Think Companies Like ARB 4x4 accessories, TJM, Opposite Lock and the Rest Exist?

Here’s a clue; it’s not because they make nice presents at christmas time ;).

Sure, some folks like to bling-up their pride and joy with aftermarket accessories to out do their neighbours ride.

But the real reason is because they make aftermarket off road gear which is needed to make today's four wheel drives off road ready. The fact that these companies exist and thrive gives you an indication of how serious the off road business is.

What Kind of 4WD Suspension Do Mid-range Four Wheel Drives Come With?

Here’s the easiest way to explain it. Today’s mid-range four wheel drives that come off the production have, what we comically refer to as, “soccer mum suspension”. This has nothing to do with gender, or even the development of future socceroo stars, but everything to do with a vehicle’s ability to work hard in the Outback.

Unlike the early 90’s, the reality is a large majority of today's four wheel drive customers are city folk looking to do city driving. This customer group either want the option to go off road one day in the future, or just need more space for the kids and their soccer boots.

What Did You Get In The Early 90’s?

trayon camper slide on camper 4wd suspension salt lake

For starters, you use to get constant load suspension!

In the early 90’s “Farmer Joe” takes a Toyota Hilux off the showroom floor, drives it straight to the farm and drops a half tonne of feed or firewood on the back repeatedly for the next 10 years, without 4WD suspension sag!”

Yes, the stiff ride of the Hilux’s constant load 4WD suspension probably knocked his fillings out and now he needs a kidney replacement, but he got that vehicle for a specific purpose. That's the purpose it was built for - hard work. That includes things like carrying the constant weight of slide on camper off road.

For that very same reason, those older vehicles didn’t suit the average person driving through the city.

What Happened Since the Early 90’s?

To capitalize on the wave of customers buying all wheel drive vehicles like Toyota RAV 4’s with soccer mum suspension, car manufacturers have since softened up 4WD suspension across most four wheel drives, thus appealing to a larger market.

The dual cab market in particular has seen a massive rise in the range of customers they attract, due to their now softer ride.

The issue is, when “Farmer Joe” gets back in today's ‘one tonne’ four wheel drive ute and loads it up, the suspension sags and drops all the weight on the bump stops. That brings us back to the point about the existence of aftermarket suspension. It exists because it's a necessity for those wanting to put their 4WD to hard work.

Do Any Vehicles Come with 4WD Suspension Ready For Hard Work?

Mercedes Benz G Professional Slide on Camper

Mercedes Benz G Professional Slide on Camper

There’s only a few vehicles left standing on the market which come off the showroom floor ready for really hard constant work. Examples of the heavy duty off road workhorse range include the 79 Series Landcruiser single cab chassis, and the Mercedes G Class Professional single cab chassis.

We’ll put it like this; we would much rather spend 9 hours on the highway carting a slide on camper in a mid-range four wheel drive, than in a heavy duty off road workhorse vehicle. That way we’ll keep our fillings, haha!

But on the flipside, we would much rather spend 9 hours on the Canning Stock Route carting a slide on camper in the heavy duty off road workhorse vehicle, than in a mid range four wheel drive. That way we’ll make it home!

This reflects the type of job each vehicle is built for, and what kind of 4WD suspension is required for that job.

So, Back to Our Recommendation!

That’s the end of our 4WD suspension history lesson.

The moral of the story is, if you own or buy a new mid range four wheel drive and you want to carry or tow weight off road, you’ll need to upgrade the soccer mum suspension.

“Farmer Joe” needs to approach an aftermarket supplier with his 2017 vehicle and get constant load suspension.

We recommend 600 kg constant load suspension, as this will prepare your vehicle for anything the Outback has to throw at you whilst carrying your slide on camper (because you may have to carry or tow things you didn't plan to!). However, 0-300 kg, or constant 300 kg is also better than your standard springs, just not as versatile as 600 kg.

The other advantage of constant load 4WD suspension is the additional clearance (usually two inches), which is very handy in the Outback to raise your vehicle up and out of harm's way or stop you from bottoming out!

trayon camper slide on camper 4wd suspension water crossing

How Does Constant Load Suspension Affect the Vehicle's Ride?

There’s no question that these upgrades will stiffen up the ride quite a bit, but it's well worth the trade off.

Because hard working, tough heavy duty suspension is MEANT to kick like a mule!! - Farmer Joe

Don’t worry, it’s not that bad! But for those who may find this an issue, here's a few good solutions which can be used separately or combined:

  • Go for a softer constant load 4WD suspension. Spring ratings of 0-300 kg or 300kg constant loads have less leaves or less coil tension. But remember, this means more potential to sag (i.e. less suspension travel/absorption capacity).
  • Upgrade to softer 4WD shock absorbers. This can help to dissipate the energy exerted by stronger springs. Just be aware that softer 4WD shock absorbers may wear quicker than firm ones, and can even overheat and be damaged in bumpy terrain (i.e. severely corrugated terrain causes more friction and thus more heat).

You can even fork out a few more rupees for some premium adjustable 4WD shock absorbers like the new ARB BP-51 range. They allow you to adjust the shock absorber from soft, medium or hard settings, giving you more control of ride quality than standard 4WD shock absorbers. They mitigate overheating issues via a removed oil reservoir - you get what you pay for!

  • Add a ballast weight to smooth out the ride, which we explain further below.

What’s A Ballast?

A ballast is a weight placed at the rear of the vehicle to smooth out the kick of stiff 4WD suspension.

For example, you can get trays installed which come with an 80 litre water tank underneath the back of the tray. When the vehicle is carrying something heavy, like a slide on camper, you don’t need to fill it up with water. The weight of the load is enough to smooth out the ride.

When the load lightens (i.e. when you slide off the camper) your 4WD suspension stiffens up, and that's where a ballast filled with water can really help to smooth out the ride and soften the blow of lumps and bumps.

What About Airbags?

Airbags are sometimes recommended as a good 4WD suspension upgrade to:

  • take the kick out of stiff springs
  • raise the height of the vehicle, or
  • support soccer mum suspension.

We Do Not Agree

  1. Airbags aren’t meant to be load carriers, they are load levelers; and
  2. They are completely ineffective off road when combined with a leaf spring suspension.

Airbag manufacturers recommend deflating the air bag when driving off road to prevent 4WD suspension damage. The damage is caused by the combination of high airbag PSI and violent shocks experienced off road.

With air bag pressure reduced, the weight ends up resting back on the underlying springs anyway, so you may as well have constant load 4WD suspension (which gives you a two inch lift as well!).

If the airbag is left over-inflated, it puts too much pressure on the wrong points of the chassis, potentially causing serious damage to your 4WD suspension or the chassis itself.

This completely defeats their usefulness off road.

Airbags Off Road - Busted!

While You’re There You Should Upgrade GVM Too

GVM refers to gross vehicle mass.

Each vehicle make and model has a unique GVM, which is the total of its own weight plus everything else it can carry. GVM is set by the vehicle’s manufacturer.

trayon camper slide on camper 4wd suspension dunes

What Happens If You Exceed GVM?

If you exceed your vehicle's specified limits, not only is it ILLEGAL, but it could:

  • Void your vehicle's insurance cover and potentially its warranty
  • Significantly increase the risk of breaking the chassis, suspension components and axles; or
  • Significantly increase the risk of injury or worse for you, your passengers and other people on the road around you.

For more information on GVM and how to calculate whether you will exceed it, check out our article ‘how to choose a slide on camper’.

It's Not Just About How Much Weight You Plan To Carry

As we have already mentioned, regardless of whether you think your loaded vehicle is under GVM, you may still push your vehicle above its GVM limits during unexpected circumstances in the Outback.

For example, if you’re travelling with another vehicle (which is the safest way to travel in the Outback) and your mate gets bogged or runs into trouble, you may need to carry or tow a heap of extra weight. Sure, you may be exceeding GVM for a good cause, but try telling that to the insurance company!

Basically you need some spare payload for unexpected situations. For this reason, a GVM upgrade to your vehicle’s absolute maximum is a very good idea, even if you think you will not exceed it.

Whats Involved with a GVM Upgrade?

If you're going to upgrade to constant load 4WD suspension, that's effectively the workshop side of a GVM upgrade anyway. The second part of the GVM upgrade is the certification.

You may have upgraded to better 4WD suspension, but without certification by a qualified person, you are still legally restricted to your current GVM on paper.

The advantage of getting your GVM upgrade certified is that you’re then covered for whatever you need to do down the track. Your vehicle is ready to take (now or sometime in the near future) upgraded bull bars, tow bars, long range fuel tanks, water tanks, suspension ballasts, plus a full slide on camper setup, without worrying about whether your vehicle is exceeding GVM and therefore illegal.

Every vehicle has limitations when it comes to GVM upgrades, as does every state and territory. So you should enquire with your vehicle's manufacturer, your government transport departments (both state and federal), and your mechanic before committing to a GVM upgrade.

trayon camper slide on camper 4wd suspension upgrade

We Recommend Getting a GVM Upgrade Before the Vehicle Is First Registered

This way, after registration, you’ve not only saved money by rolling it all up in one 4WD suspension upgrade, you now have a vehicle that is immediately ready for anything, such as:

  • difficult off road terrain
  • any combination of vehicle accessories; and
  • heavy loads.

Does Vehicle Make or 4WD Suspension Brand Matter?

Yes, it matters. But we won’t be entering into the brand debate.

There’s so many brands of everything out there, all with their own pros’ and cons’, and subject to varying opinions, reviews and experiences, that it's not worth complicating this post with brands.

All we can say is we have a long standing relationship with ARB and we’re confident in sending Trayon customers their way for suspension upgrades. The advantage is they have workshops all over Australia.

4WD Suspension Summary

Let's bring it all back to the start, and summarise our advice.

At a minimum, for 100% bitumen driving (or very close to), better quality 4WD shock absorbers will do the job.

If you plan on leaving the bitumen, even with a lightweight slide on camper, you should aim for 600 kg constant load 4WD suspension and better quality shock absorbers to dissipate the extra kick. Once this is being done, you may as well get the GVM certificate with it for only a few extra dollary’ doos.

If ride stiffness is a real concern, you can try constant load 4WD suspension with lower weight ratings, softer (or adjustable) 4WD shock absorbers and/or install a ballast.

Our Final Tip

trayon camper slide on camper 4wd suspension convoy

Although important, these 4WD suspension upgrades are just recommendations. They will not make any vehicle invincible.

Even with good gear, while driving long distances in the rough conditions of the Outback, break something you will! People often grossly underestimate the impact of Australia’s offroad conditions on their vehicles.

That's why its so exciting, and also why the most beautiful untouched destinations are found at the end of a long dirt track. Who knows what will happen! But with adequate preparation, responsible driving to the conditions, and the right off road gear, you can have more control over your own fate. Victory favours the prepared!

No amount of suspension work will compensate for irresponsible driving.

ENQUIRE NOW

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