One of the easiest and most effective changes you can make to an outback touring vehicle is a set of good tyres. But which tyres are best for the outback?
Choosing tyres for your outback tourer
As an outback tourer, you're going to ask your tyres to cover tens of thousands of kilometres over bitumen, gravel, rocks, sand, and a little bit of mud.
You're going to ask them to do it at high temperatures, while supporting a lot of weight and running at reduced pressures. They will face razor sharp stones on the gibber plains and iron-hard spikes in the mallee; red hot sands in the Simpson and foul sticky clay in black soil country. And a puncture has to be repaired yourself, right there... there's no roadside assistance out here.
This is a completely different set of demands to the weekend warrior who wants to tackle the tracks in their local patch of forest, or to the urban SUV driver who thinks "off road" is the graded gravel road to their favourite picnic spot.
The standard tyres fitted to most new 4WDs are the worst kind of compromise. They're bad at nearly all of these tasks, and simply aren't up to the abuse that the outback will throw at them.
For most modifications, my philosophy is to spend a little bit of time working out how the stock setup works (or doesn't) before rushing out and spending money. But this is not true for tyres. If you do nothing else to your vehicle before hitting the outback, get a good set of tyres. With the right tyres and the right attitude, just about everything else in the accessory catalogue is optional.
All terrain vs mud terrain
One of the most common questions for people setting up their outback touring vehicle is AT or MT tyres. It seems like everyone has a preference.
The truth is, there's pros and cons to each, and these days there is less and less difference between them. If you're new to all this, the guys over at RV Daily have a really good guide to the difference between passenger, light truck, HT, AT and MT tyres. Check it out here.
Let's take highway (HT) tyres out of the picture straight up. They're great (obviously) on the highway. They're pretty good in sand. And they're surprisingly decent on gravel too. But they're useless in mud or over rocks, and almost no one makes HT tyres with decent carcass strength that will survive prolonged use off road.
Fans of AT tyres will tell you they offer the best possible compromise between all of the tasks you will ask of an outback touring tyre. They offer 90% of the performance of a highway tyre on the road, 90% of the performance of a mud tyre in mud, and are the best option for the high speed gravel that paves most of our outback 'highways'.
Fans of MT tyres will tell you they offer the longest tread life, best puncture resistance, strongest construction, and offer the best performance for most off-road situations in exchange for slightly reduced performance on the highway.
Sorting the facts from the myths
Unfortunately, like a lot of 4WD "wisdom", some of the opinions out there about AT and MT tyres are decades out of date, or just plain wrong.
Myth: AT tyres can't handle mud
AT tyres are definitely not as good in deep, sloppy mud as dedicated mud tyres are. However, they won't hitch up their skirts and run away either - modern AT tyres are pretty effective at self-cleaning, and their main difference to modern MTs is they lack deep shoulder lugs and side biters (tread on the sidewall of the tyre). These are useful in deep muddy ruts, but less so in the sticky mess of clay that characterises a lot of mud in the outback.
In most outback mud, I give MTs a 10/10 score and ATs 8/10.
Myth: MT tyres are scary on the road
This was probably true 15-20 years ago, and it remains true for specialist competition-grade mud tyres now. But most mud tyres on the market these days have pretty good road manners. Yes, you will notice a difference compared to highway tyres, especially in wet braking and cornering. But not to such an extent you will fear for your life.
For sealed road performance, I give MTs 7/10 and ATs 8/10.
Myth: MT tyres are more puncture resistant
This is another 'fact' that was probably true 10-15 years ago, when there weren't very many heavy-duty AT tyres available and when mud tyres often had an insanely stiff carcass. These days, there is no shortage of heavy-duty AT tyres available, and the design of MT tyres has improved - that's one of the reasons their road and sand performance has improved so much.
Let's call this one even.
Myth: MT tyres are no good on sand
This myth is related to the one about puncture resistance: once upon a time, MT tyres were extraordinarily stiff, and you just couldn't get the pressures low enough for use on sand without risking a bead popping off (or pinching a tube, if you're that old!). This just isn't true anymore. Hypothetically, the more aggressive tread of a mud tyre will 'dig' more than the smoother tread of an all-terrain, but we're talking very small degrees of difference that you probably won't notice at the wheel.
For sand use, I give ATs a 9/10 and MTs an 8.5/10.
Myth: MT tyres have longer tread life
OK, let's call this one partly true. MT tyres usually have deeper tread than AT tyres, and so if you call a tyre 'worn out' when it gets to the legal 1.5mm minimum tread depth, they will last much longer than an AT. However, if you call a tyre 'worn out' when it has developed uneven wear, the tread blocks are cut and chipped and too shallow to be useful off road, and it begins to scare you on roundabouts in the rain, then AT and MT tyres will last about the same if all other things are equal.
This is another tie.
Fact: MT tyres are noisy
This one is true, especially as they age. AT tyres are noisier than HT tyres, but MT tyres dial that up again. There are a few designs that claim to be especially quiet, but this is like saying Metallica are less metal than Pantera - it's all relative. If you value a smooth quiet ride, you should stick to all-terrains.
To be fair, this is pretty much the only serious drawback to mud tyres, and if you have a bunch of stuff howling in the breeze on your roof rack or a big noisy diesel, you might not notice much difference from inside the cabin.
For noise, I give MTs a 5/10 and ATs 7/10.
Fact: MT tyres reduce your fuel economy
This is also true. AT tyres will reduce your economy compared to HT tyres. MT tyres make it worse again. The difference not huge and it's getting smaller and smaller all the time, but you will notice it if you monitor your fuel economy.
For fuel consumption, it's AT 8/10 and MT 7/10.
I genuinely don't think you can go wrong with any quality-brand AT or MT tyre with an appropriate load rating and light truck construction.
I prefer AT tyres, because for the driving I do the advantages of MTs aren't enough to offset their reduced on-road performance and extra noise. They're also usually more expensive. I look for a tyre that's easy to buy (no obscure brands that you can only buy in city specialist stores), has a load rating of 120 or better, and has a solid reputation in the Australian market.
This is based on my experience with everything from rag-and-tube tyres on a Series III Land Rover to top-brand muddies on a Landcruiser. The way you use your tyres might be different to me, and you might value different things. That's fine - let me know in the comments!
Don't just listen to me: There are a couple of different schools of thought out there that you should have a think about.
Tubes for the win!
When most people, including me, talk about 'off-road' driving, we really mean 'rough road' driving. There is at least a pair of wheel tracks to follow, no matter how old and overgrown they are. For some people, such as gold prospectors and the hardiest adventurers, 'off road' means literally that - crossing virgin scrub where no vehicle has ever driven before.
Mick Hutton and his wife Connie Sue Beadell (yes, that one, for whom the Connie Sue Highway is named) know more about this kind of outback driving and more about tyres than just about anyone else alive. Through their business Beadell Tours, they swear by bias construction tubed tyres for the truly hard core desert explorer.
Mick's website has a wealth of information about tyres, including a list of all the failures he and his clients have had over the years. Do yourself a favour and set aside an hour or two to read what he has to say.
There is a relatively new kind of tyre hitting the market that is somewhere between an AT and MT tyre. It usually has the aggressive shoulder lugs and side biters of an MT, but the more mild centre tread pattern of an AT. Without plugging any one brand over another, examples include the Nitto Ridge Grappler, Goodyear Wrangler Duratrac, and Kumho MT51.
I think the jury is still out on whether these are a genuine improvement on either the AT or MT market, but most major manufacturers now have a design like this.