So, we've decided to upgrade our 2018 Swift Challenger 480 (2 berth) and are searching for a suitable 4 berth. We will be towing it with our 2019, 240bhp Volvo XC60 T5 (petrol) Inscription. Many of the caravans we are now looking at are twin axles. Having never towed with a twin I could do with some background info regading pros and cons. Apart from the obvious advantage that heavier vans are more stable with 4 wheels than 2 and the disadvantage that 4 tyres are more expensive to replace than 2 is there anything else to be considered? I'm sure there is. For example do it need 4 motor movers or will one either side suffice? Any tips gratefully received.
Twin axle pros and cons?
- Thread starter Banus
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- Mar 14, 2005
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The chassis of a caravan with two axles obviously weighs more than one with a single axle, thus increasing the MIRO and consequently reducing the payload potential within a particular MTPLM constraint.
A twin axle is less manoeuvrable than a single axle and tends to churn the grass up more when pitching. For this reason, some campsites, particularly on the Continent, won't allow them.
A twin axle is less manoeuvrable than a single axle and tends to churn the grass up more when pitching. For this reason, some campsites, particularly on the Continent, won't allow them.
- Jun 20, 2005
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There are plenty of SA available that have greater weights than a TA. Adria for example.
I’ve had both.
But you must ensure whatever you choose
Your car is capable of handling the MTPLM
You fully understand setting up, the weight balance within the caravan itself.
Ok , assuming all correctly loaded.,so I’ve had both. No question the TA is more stable, less prone to being affected bysevere crosswinds.
A quad drive MM is an over kill imo. We have a simple Powrtouch single fitted on the front axle.
Easy to use but be patient . No pirouetting like a SA but easily managed
I’ve had both.
But you must ensure whatever you choose
Your car is capable of handling the MTPLM
You fully understand setting up, the weight balance within the caravan itself.
Ok , assuming all correctly loaded.,so I’ve had both. No question the TA is more stable, less prone to being affected bysevere crosswinds.
A quad drive MM is an over kill imo. We have a simple Powrtouch single fitted on the front axle.
Easy to use but be patient . No pirouetting like a SA but easily managed
- Mar 14, 2005
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You cannot avoid the side scrubbing of tyre when you have a TA. They are almost impossible to turn if you are manually trying to position it. A caravan mover is a big assistance - Some single axle mover must not be used on TA's Follow the mover manufacturers adv
Some users of TA's swear they tow better, and that will be a matter of personal experience, but part of the possible reason is that TA caravans tend to be longer, and that can reduce some of the forces that contribute to instability.
When hitched, longer caravans (SA of TA) are generally easier to reverse around corners as the trailer is slower to try to jack knife.
Proper tyre inflation is just as important on both the car and caravan.
Nose load (A contentious issue) becasue of the geometry of the suspension and its interaction with the caravans centre of gravity, it's more important than ever to ensure your nose load is set correctly for the height of the tow hitch when the trailer is coupled.
Some users of TA's swear they tow better, and that will be a matter of personal experience, but part of the possible reason is that TA caravans tend to be longer, and that can reduce some of the forces that contribute to instability.
When hitched, longer caravans (SA of TA) are generally easier to reverse around corners as the trailer is slower to try to jack knife.
Proper tyre inflation is just as important on both the car and caravan.
Nose load (A contentious issue) becasue of the geometry of the suspension and its interaction with the caravans centre of gravity, it's more important than ever to ensure your nose load is set correctly for the height of the tow hitch when the trailer is coupled.
- Jul 18, 2017
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We started off with a SA and then about 20 years ago we switch to a TA and never looked back. A lot easier to tow plus a lot more room inside especially if it is a 8' wide caravan.
On many sites, the roadways are gravel so scrubbing is not an issue and if using a AWD motor mover scrubbing is reduced significantly. It never bothered us. Many TA caravan also have an onboard tank. If we had to start again, I doubt very much if we would look at a SA again.
On many sites, the roadways are gravel so scrubbing is not an issue and if using a AWD motor mover scrubbing is reduced significantly. It never bothered us. Many TA caravan also have an onboard tank. If we had to start again, I doubt very much if we would look at a SA again.
- Sep 4, 2011
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Over the years we have had many Caravans 5 berth 4 berth and 2 berth. Even the largest Caravan towed faultlessly and a single axle. Single axle is more easily moved when unhitched. Twin axles if on soft grass or gravel without movers on all wheels we have seen times the driven wheels just skid and dig in.. We personally have never seen the point of towing more weight around than needed. Main thing is the layout you like regardless of number of axles.
We have had 9 caravans so far, 2 were twin axle, the extra space inside is useful if you need it, the xtra size outside can be a pain on site, and depending on what your storage arrangements are, TA tend to mean extra costs, insurance, tyres, servicing,
As you are going from 2 berth I suggest you look at layouts first, find the one that suits you, and then look for the layout in TA and SA, sit in both, and then decide if the extra space etc justifies the extra cost, good luck with whatever you decide
As you are going from 2 berth I suggest you look at layouts first, find the one that suits you, and then look for the layout in TA and SA, sit in both, and then decide if the extra space etc justifies the extra cost, good luck with whatever you decide
- Mar 14, 2005
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I don't know of many twin axle caravans that are bigger than my single axle, so that's not really a valid argument.
- Mar 14, 2005
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I don't see the double axle caravan necessarily gives more room, nor up to quite high weight levels, greater weight capability.
The latter might have been the case back when SA chassis could not carry the mass they can today, however even when we last purchased in 2007 our SA had a 1900kg Alko light weight series chassis.
Not long after that Alko upped the light weight series to 2000Kgs and I believe with the light series they have gone higher, 2100kgs?
Caravans up to the 2000kg will cover I suggest most of the range we as UK vanners purchase for other reasons? So, in fact most of us don't actually need a double axle to carry the vans of the weight we choose to own. The picture changes where very large vans are concern, there being over the weight limit of SA caravan chassis, there is no light chassis alternative.
The double axle in like for like cases lose more internal space because of the greater length of wheel arch intrusion. Along with this comes the greater compromise on layouts because of these longer wheel arches within the van.
The double axle does tow quite a bit less twitchily in yaw simply because the damping from the tandem tyres inherent resistance to track other than in a straight line.
However, this less twitchy state should not be confused with critical stability, as once the energy builds up a twin axle can certainly go seriously unstable. The SA in this respect is different in that it tends to remind you its getting unhappy before it literally "throws a wobbly".
Choice might also be effected by the intended type of campsites and camping used. On hard surfaced sites and accesses the twin raises no issues, but go off the hard stuff onto grass the inherent resistance to turning results in the ground being torn as the easiest relief of the tyre windup. From that the rallying and 5 van site type caravanners "tend" to keep to single axle vans, at least if they care for the interest of site owner's and follow on users.
This tyre resistance I have found can bring a plus in it provides a bit of reticence to turn that gives reversing a "softer" manner. This can make things easier, at least for those of us not masters at reversing, even if probably making positional precision less easy to achieve by those that are.
Other pluses for twins, the wheels are way lighter to manhandle, and come a full on puncture you might be able to coast to the nearest layby .They seem to run lower tyre pressures so each individual tyre is more compliant which has to yield a softer ride over harsh surfaces.
For our own needs I would now only buy a SA, but that is because of our particular needs, our camping and our maneuvering challenges at home.
The latter might have been the case back when SA chassis could not carry the mass they can today, however even when we last purchased in 2007 our SA had a 1900kg Alko light weight series chassis.
Not long after that Alko upped the light weight series to 2000Kgs and I believe with the light series they have gone higher, 2100kgs?
Caravans up to the 2000kg will cover I suggest most of the range we as UK vanners purchase for other reasons? So, in fact most of us don't actually need a double axle to carry the vans of the weight we choose to own. The picture changes where very large vans are concern, there being over the weight limit of SA caravan chassis, there is no light chassis alternative.
The double axle in like for like cases lose more internal space because of the greater length of wheel arch intrusion. Along with this comes the greater compromise on layouts because of these longer wheel arches within the van.
The double axle does tow quite a bit less twitchily in yaw simply because the damping from the tandem tyres inherent resistance to track other than in a straight line.
However, this less twitchy state should not be confused with critical stability, as once the energy builds up a twin axle can certainly go seriously unstable. The SA in this respect is different in that it tends to remind you its getting unhappy before it literally "throws a wobbly".
Choice might also be effected by the intended type of campsites and camping used. On hard surfaced sites and accesses the twin raises no issues, but go off the hard stuff onto grass the inherent resistance to turning results in the ground being torn as the easiest relief of the tyre windup. From that the rallying and 5 van site type caravanners "tend" to keep to single axle vans, at least if they care for the interest of site owner's and follow on users.
This tyre resistance I have found can bring a plus in it provides a bit of reticence to turn that gives reversing a "softer" manner. This can make things easier, at least for those of us not masters at reversing, even if probably making positional precision less easy to achieve by those that are.
Other pluses for twins, the wheels are way lighter to manhandle, and come a full on puncture you might be able to coast to the nearest layby .They seem to run lower tyre pressures so each individual tyre is more compliant which has to yield a softer ride over harsh surfaces.
For our own needs I would now only buy a SA, but that is because of our particular needs, our camping and our maneuvering challenges at home.
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- Jul 18, 2017
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Just to add the double axle loses zero usable space because of wheel arches. Our twin axle gave us a lot more room than any SA we previously owned, but admittedly this was way back in 2005.
Although we would never consider buying a SA again due to lack of space and payload, it is up to the individual to decide which layout is best for them whether SA or TA and what their vehicle is capable to towing.
Although we would never consider buying a SA again due to lack of space and payload, it is up to the individual to decide which layout is best for them whether SA or TA and what their vehicle is capable to towing.
- Mar 14, 2005
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Unless you are comparing the exact same design of caravan, your claim that "Our twin axle gave us a lot more room than any SA we previously owned" is counter to any logical thought process based on th e number of axles..
Twin axle caravan rob more volume from a caravan body by virtue of the intrusion of more or larger wheel arches. Thus a TA of exactly the same size as an equivalent SA can never provide more internal body space simply becasue it's a TA! If greater useful space is available, it can only be derived by better utilising the internal space, and that is down to the design of the internals, not the number of axles.
If you have found TA's with greater useful space than SA's were the caravans the same size and design? Ill guess they weren't.
- Jul 18, 2017
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Not sure why you are looking for an argument again? Did you own any models of the SA and TA caravans that we owned. From OUR perspective, we had a lot more room than in a SA.
- Jun 20, 2005
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20 years ago and I believe the same can be said today, Bailey , Swift, Elddis and Coachman do not make a SA equal to or larger than their TA
Adria, Knaus and probably another EU maker do make large SA but the numbers are low.
Thus I can say with personal experience the U.K. made TA is going to give more cubic capacity (sic). than the available SA. Of course the extra wheel arch is an intrusion but with clever design it does not intrude into the usable space.
The OP has a Volvo which can cope with anyTA available in the U.K. .
I have already said a 4 wheel mover is an overkill imo. My Powrtouch heavy duty moves the TA easily but turns have to be taken slowly and sometimes a little to and froeing. Yes scuffing is inevitable on grass. Hard standings no,propblem.
OK every five years or so I buy 4 new tyres not 2. Maybe an extra £150. Not much in relation to the whole outfit.
As for moving it by hand , forget it! I doubt I could push pull a 1800 kgs SA😉
This link from Al-ko clearly demonstrates the number of large SAs is minimal.
https://www.trailer-center-discount...d-axle-900-2000kg-delta-axle-type-si-n-axles/
Note the axle loads and price compared to a much lighter SA. Plus in my case I have two ,1000kgs rated axles each of which is considerably cheaper than one at 2000kgs. It’s all relative 😉
I hope some of the constructive comments help the OP reach a decision🤔
I hope he lets us know his final choice😎
Adria, Knaus and probably another EU maker do make large SA but the numbers are low.
Thus I can say with personal experience the U.K. made TA is going to give more cubic capacity (sic). than the available SA. Of course the extra wheel arch is an intrusion but with clever design it does not intrude into the usable space.
The OP has a Volvo which can cope with anyTA available in the U.K. .
I have already said a 4 wheel mover is an overkill imo. My Powrtouch heavy duty moves the TA easily but turns have to be taken slowly and sometimes a little to and froeing. Yes scuffing is inevitable on grass. Hard standings no,propblem.
OK every five years or so I buy 4 new tyres not 2. Maybe an extra £150. Not much in relation to the whole outfit.
As for moving it by hand , forget it! I doubt I could push pull a 1800 kgs SA😉
This link from Al-ko clearly demonstrates the number of large SAs is minimal.
https://www.trailer-center-discount...d-axle-900-2000kg-delta-axle-type-si-n-axles/
Note the axle loads and price compared to a much lighter SA. Plus in my case I have two ,1000kgs rated axles each of which is considerably cheaper than one at 2000kgs. It’s all relative 😉
I hope some of the constructive comments help the OP reach a decision🤔
I hope he lets us know his final choice😎
No, Admin please remove and place in the fridge issue one; put it down to getting senile.
- Feb 13, 2024
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Changed son's 4 thirteen inch tyres for roughly the same price as our larger pair, and they run at 35 psi compared to our 56 psi so i don't think the tyre cost is much of an issue
- Feb 13, 2024
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- Jun 20, 2005
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See #3 . I said just that . My point was the large SA axles actually cost more that one TA axle. It’s all relative
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