It’s now coming into that time of year where grey nomads rule the road. Before you pull the cover off the caravan and set off to your next destination, it would be wise to do a few safety checks. One of the most overlooked items is tyres.
After spending more than a decade driving professionally, I’ve learned a few key points about looking after tyres, because no one wants to ruin a trip with a blown tyre or the hassle of changing a tyre in the summer sun.
A blown tyre can cause all sorts of damage to a caravan/camper. The worst-case scenario is if it completely lets go and explodes, as this can do damage to the structure of the caravan. The sharp wires from the carcass can damage the exterior of the van, the chassis and suspension components. Cuts, tears and punctures to air bags can also occur. This is definitely no fun on a holiday! Adding mechanical repair bills and towing bills could really ruin a planned vacation away.
The caravan tyre itself
So, first things first - understanding the life of a tyre on a caravan. It’s easy to think, “It’s behind me, so why do I need to even worry about it, I’m only towing”. Unfortunately this attitude is seen far too often.
The most common car today for towing is the dual cab ute. The common dual cab utes on the market weigh roughly 2,400-3,000kg when loaded up. That’s roughly 600-750kg on each tyre, which isn’t too bad.
Now here’s the scary part - the average caravan can range from 2,200-3,000kg on a single axle. That’s 1,100-1,500kg on each tyre, yikes! So straight out of the driveway your caravan tyres are under double the stress of a car tyre. It’s absolutely key to be sure you have the correct tyre before you set off. This means having the correct construction and load rating of the tyre.
Types of tyres used
Unfortunately, not all tyres are the same. Every tyre is built differently, so I’ll run through a few things to look out for.
Understanding the load on the tyre is important. This helps you to select a tyre with the right load index. The load index is located on the sidewall of the tyre along with all the other mumbo jumbo numbers and symbols. The load index will be a number ranging from 62 to 126, the higher the index the heavier the rating. You can find the
Tyre Review load index here. You need to run a tyre with a load rating higher than your maximum weight – basically, the higher the better.
There’s also an index on the tyre which is a speed symbol, but unless you’re planning on entering a caravan race or trying your luck at the local drag strip, the speed symbol isn’t much of an issue as most tyres are rated for higher than Australian speed limits. The speed symbol is a letter in the sidewall of the tyre ranging from J to ZR. J being 100km ZR being 240km. K is 110km so anything above that is fine.
The construction of the tyre is important, too. You really want the toughest, most robust tyre you can get. Choosing a tyre with a high load rating normally means the tyre is going to be a lot stronger and have more sidewall stability. This is a huge positive for towing as the more stable the tyre is the more control you will have too.
So, the thing to look for is the letters LT after the size of the tyre. This stands for Light Truck. LT tyres will have more reinforced layers throughout the tyre, and this makes them stronger, less prone to blow outs and less likely to get a puncture from sticks, road kill, glass or anything else that the road may throw at you.
There’s also the term 3 ply sidewall. These tyres are great as they add stability and also make the side wall stronger. For example, if you didn’t see a metal stake post or left over ground peg that might want to make an entrance through the side wall, the 3 ply will help stop that from happening.
The last point of tyre selection is the tread pattern. There are three main types of tyres - highway tyres, all terrains and mud terrains. It’s pretty easy to decide on the right tyre for your application:
If your driving is done on the black top, grab a set of highway tyres.
If you’re planning on heading to the beach, or taking dirt and gravel roads to the more sneakier camp spots, all terrains might be the way to go. Keep in mind that this doesn’t mean one tyre type can’t do the other. Having highway tyres can work well on the sand too, with the correct tyre pressures.
Then there’s the mud tyre... the mud tyre seems to be making more of an appearance lately on off-road caravans, and in my opinion it actually has no advantage. In fact, I believe it’s more of a disadvantage, and here’s why:
The mud terrain is designed to have taller tread blocks and larger voids to dig into mud and clean away mud when spinning the tyres, which you can’t do with a caravan. So rather than cleaning, it’s just capturing the mud.
The voids are also fantastic at capturing tiny little stones and gravel, both on the road and off-road, then flicking them all down the side and rear of the caravan making a mess and causing damage.
Another thing to consider is with the tread blocks being so tall with larger voids on the highway, it reduces performance and the tyres tend to squirm and walk on the road. Unless none of that bothers you, I don’t recommend mud terrain tyres. A durable set of all terrains will fill the role well on the van and you can still run a set of MTs on the tow vehicle.
The caravan tyre after storage
Let’s say that you already had the greatest tyre you can buy on your van, but the caravan has been stored for a few months and you’re planning a fairly decent trip away. Here are some tips for maintenance and care before venturing off into the great blue yonder!
A couple of weeks prior to your departure date, I recommend doing a simple check, which is just a brief look at the tyres. Take a look at the sidewall for any surface cracks, colour fading or signs of fatigue. These signs will be significantly more noticeable if the caravan is stored uncovered, as the tyres will be going through heat cycles with the changing of day and night temperatures, as well as lots of UV rays. Also there is a 4 digit number on the tyre which will
indicate when the tyre was made.
Another obvious point to make is if the tyre is flat or doughy there may be a slow leak somewhere, and you’re best to have it looked at by a tyre shop. Slow leaks can be anything from a leaky valve, small hole, or worse, a damaged or cracked rim, which can happen with aftermarket rims that don’t have correct load rating. It can also happen if they’ve copped some abuse on the last trip you took.
If you need to change a tyre it’s definitely a good idea to have the tyres on the same axle at roughly the same tread wear depth. For instance, if you get a flat tyre that needs replacing, and the other tyre is only half worn, it’s best to replace them both. This is because having different tread depths can create imbalance, particularly in emergency situations.
If the tyre looks good, that’s great. The next top tip would be to go for a drive, say half an hour or so. This will do many good things. Firstly, it warms the tyres up and gets them moving, which will expose any new surface cracks on the sidewalls. Secondly when a caravan is parked for long periods of time the footprint of the tyre tends to form a flat spot, and by driving around moving the tyre and warming it up, this tends to release that flat spot. If it doesn’t then you might be best to get it checked out.
If your tyres all check out ok, the last thing I would recommend before a trip is to have the tyres rotated, and have a wheel alignment done to the caravan.
Tyre pressure
Tyre pressures are a slightly confusing topic, as there is no exact pressure that is perfect. If you go to 3 different tyre shops, you will more than likely get 3 different answers.
Your caravan will come with recommended tyre pressure, which, in my opinion, are usually on the low side. However, keep in mind that this tyre pressure is set when the tyres are cold. As the tyres are driven, they will heat up and the air pressure will increase. There’s a big difference between cold tyre pressure and hot tyre pressure. Other variables are the outside temperature, the road temperature and the weather.
Ideally you want your tyres to look uniform across the tread pattern, and the best way to tell if your pressures are right is by tyre wear. If your pressures are on the low side your tyres will wear unevenly on the shoulders. You may find it’s wearing faster, getting a saw tooth effect, or even developing slight scalloping. If the tyre pressures are too high, then the centre will wear out quicker.
There’s pros and cons for both low pressures and high pressures, so I’ll run through them.
Low air pressure in caravan tyres
Low pressure gives you a longer footprint of the tyre and adds extra traction. The downside is that it adds more rolling resistance and fuel consumption. Tyre life decreases, while the comfort level increases as the tyre can absorb more bumps.
High air pressure in caravan tyres
High pressure gives you less traction as the footprint decreases. This gives you less rolling resistance and the fuel consumption decreases. The comfort level will also decrease as the tyre can no longer absorb the bumps as easily.
If you run the tyre pressures on the lower side of the scale the tyre will heat up more and in return increase the pressure. If you run the tyre pressure on the high side the tyre will heat up less and in return there will be less of an increase in pressure.
The weather and outside temperatures will also have an effect.
Winter
In the winter time or cold wet conditions, I choose to run my tyres on the lower end of the air pressure scale. This way the tyre has more grip for safety and can warm up for better traction without overheating. When looking at the tyre, I’m aiming for a slightly larger, lower half bulge then the top half.
Summer
In the summer time I tend to run the pressures a lot higher. This way I’m limiting the extra heat added to the tyres. Being summer you tend to experience hotter conditions. The roads will be hot and tyre temperatures will be high, so I tend to have more rest stops to let the tyres cool down. I also tend to go a little slower on the highway, being conscious not to add any more heat into the tyres. I also tend to check my tyres more regularly, looking for signs of uneven wear, damage and I feel the heat of the tyre. The last thing I want to do is change a tyre on a road that you can cook eggs on!
Hopefully now you have more of an understanding of the safety and durability aspects of caravan tyres, so that you can stay safe and keep it sunny side up!
About the Author
Chris Thomas is a passionate 31 y/o truck driver with over 7 years trucking experience driving road trains the 8000km round-trip between Sydney and Darwin. He says:
“A road train may have up to 4 trailers but I’ve taken key lessons from driving the 50m+ trucks over to driving a caravan on holidays. They both share the most common break down and that’s flat tyres. I’ve learnt many aspects to driving over the years and it’s always good to take that knowledge across to caravaning. The biggest lessons learnt are knowing when the body is mentally fatigued or physically tired to avoid the deadly micro sleeps. Knowing how to maintain and care for my wheels and tyres is key to avoid flats or blow outs. But the biggest point is knowing how to share the road with others to get to my destination safe and sound.”
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