single or twin axles

[pluckyducky]

I am going to buy a new caravan probably at the NEC while we like twin axles but we have only ever had single axles.
What are the pros and cons for twin axles we have a Volvo XC90 towcar so weight is not an issue I keep the caravan at home and it is up a little incline but would get a motor mover when I buy it. It will be a 4 berth

 

[ProfJohnL]

I am going to buy a new caravan probably at the NEC while we like twin axles but we have only ever had single axles.
What are the pros and cons for twin axles we have a Volvo XC90 towcar so weight is not an issue I keep the caravan at home and it is up a little incline but would get a motor mover when I buy it. It will be a 4 berth

Don't be overwhelmed by the urge to buy at the show, By all means look and get information, but take some time to check if you cant get a better deal at a more local dealer. Don't forget that your legal rights under Sale of Goods rests with the seller, which may end up being at the other end of the country! - inconvenient if you need to get something sorted out that is not covered by the manufacturers guarantee.

On the basis you have had single axle caravans, the main practical differences are, Cost - TA's are likely to be more expensive to buy, service, maintain, and repair. They have 4 tyres to replace on a regular age basis.

You will need a caravan mover, as TA's are very very very difficult to turn by hand. (the mover eats up some payload capacity)

check the payload capacity is enough for your needs. Some SA caravans of the same size can have more payload!

There are some isolated reports of storage site costs being higher for TA's, and some holiday sites charging more.

Make sure you have the means to properly measure the nose weight load, as TA's are very sensitive to hitch height affecting nose load.

There is no conclusive evidence that proves TA's are better or safer to tow, as always good towing is about sensible loading, proper maintenance of car and caravan, and good driving habits.

 

[pluckyducky]

Thanks will use the NEC as a guide didn't think about the extra costs and will check the sa at the same time

 

[chrisbee1]

As the Prof rightly says, there is no evidence that a TA is more stable to tow. However, my personal experience is that since changing from a single to a TA my outfit seems less prone to outside influences (i.e. wind and truck bow waves) than before. I like to think that both outfits were properly loaded etc.
I have also been refused entry to some sites in France because of the twin axles.

 

[pluckyducky]

Thanks again, will take all this onboard

 

[PaulT]

I agree with Chrisbee, since we changed to a TA there is a perception that the whole outfit is more stable. I'd certainly like to think that in the event of a tyre blowout, the TA would remain under control for longer.
I've never had a problem with getting onto French sites but I always take the precaution of booking in advance and telling them that it is a TA - no one has refused me yet.

 

[FrenchChuffed]

I would always go for a twin axle having towed for the past 50 years mainly boats but caravan for the last 20. I was told to tow a boat through the middle of Wolverhampton the day after I passed my test and launch it on a slipway, I worked for a boat hire firm. Car and boat survived the experience.
Twin axels give more lateral stability (despite what others will say) it must be a fact as one of the disadvantages is they are difficult to manoeuvre when pushing them on a campsite. The tyres are under less weight stress, there is more breaking surface area, and in the case of a blowout its less catastrophic. There are problems with some caravan parks in France but hopefully if pre booked would be ok.

 

[Dustydog]

Long ago I had 12ft Ski caravan. Very susceptible to passing coaches and winds.
The last SA was nearly 24ft. She was very stable .Our TA is longer again, heavier and very Stable.
Overall comparing TA and SA units the length imo adds to stability as well of course the actual loading and weight distribution.
Length for length I'd say there is very little in it.
We chose the TA because of the layout no other reason.

 

[Raywood]

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room. The safety advantages are not proven but there has to be better stability if you suffer a blow out and the second axle will create more resistance to help avoid instability.
The downside is they weigh more, are more difficult to reverse, cost more, and will use more fuel due to the drag of the second axle. There can also be problems abroad with the longest ones as many sites limlt you to an 8 m length.
At the end of the day your priorities will driv you to your choice.

 

[TheTravellingRooster]

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room. The safety advantages are not proven but there has to be better stability if you suffer a blow out and the second axle will create more resistance to help avoid instability.
The downside is they weigh more, are more difficult to reverse, cost more, and will use more fuel due to the drag of the second axle. There can also be problems abroad with the longest ones as many sites limlt you to an 8 m length.
At the end of the day your priorities will driv you to your choice.

Hi pluckyducky and Ray. I have been towing caravans and large trailers since 1966,I have towed al-kinds with al-sorts including commercial vehicles from Ford Escort Vans in the lighter range to 3ton Austin,Bedford and similar very large panel vans.

Generally speaking if a trailer/caravan is correctly loaded and weight is distributed wisely and the towing vehicle is equally taken care of then there should not be an issue baring a Blow-out.
Load weight,noseweight are critical as are correct tyre pressures and tyre condition are both crucial on both tow vehicle and trailer/caravan.
In my own experience a twin axle unit will always make for a much more relaxed towing experience and when it comes to bow waves and other influences there is considerably less trailer/caravan telling the tow vehicle what it is going to do rather than the trailer/caravan just following along behind.

Personally,I would never go back to a single axle trailer/caravan - ever. The extra body length is easily and fairly quickly adjusted to but good towing mirrors are essential - mine are Milenco Grand Aero and are used in the Portraiture mode.

The comments about the twin axle caravans being more difficult to reverse is a matter of experience - or lack of it. They are less likely to whip around on you because they do not pivot on just two wheels. They require a little more consideration because of the slower action and wider sweep needed when reversing because of the squirm created by four wheels/tyres on the surface as opposed to just two of a single axle caravan/trailer.

 

[Gagakev]

Raywood said;

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room.

Hi Raywood my van a Fleetwood is 7.95m long with an internal measurement of 6.7m with MTPLM of 1700kg
and it's a single axle. So not necessarily fixed in stone.

 

[FrenchChuffed]

Raywood said;

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room.

Hi Raywood my van a Fleetwood is 7.95m long with an internal measurement of 6.7m with MTPLM of 1700kg
and it's a single axle. So not necessarily fixed in stone.

But I would much prefer a van that size 7.95m long to have T/A's.
Just for interest what's your tyre pressures?

 

[TheTravellingRooster]

Raywood said;

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room.

Hi Raywood my van a Fleetwood is 7.95m long with an internal measurement of 6.7m with MTPLM of 1700kg
and it's a single axle. So not necessarily fixed in stone.

But I would much prefer a van that size 7.95m long to have T/A's.
Just for interest what's your tyre pressures?

Hi FrenchChuffed . Just as a point in passing. My Twin Axle 2001 Elddis Crusader SuperSirocco has a shipping length of 7.876mtrs.
It has an MTPLM of 1750kgs and a published MiRO of 1426kgs.
It runs on 175/65SR tyres with a recommended tyre pressure of 35psi albeit I have found that 38psi to be preferable.

The longer shipping length of the Fleetwood when compared to my SuperSirocco is most likely down to a longer 'A' frame that was often what Fleetwood were known for. It gives a more stable towing experience - I had a 1992 Fleetwood Colchester 1850 and it towed as straight as an arrow albeit a trifle heavy on the nose when empty and until balanced to my required 75kgs.

 

[Gagakev]

Raywood said;

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room.

Hi Raywood my van a Fleetwood is 7.95m long with an internal measurement of 6.7m with MTPLM of 1700kg
and it's a single axle. So not necessarily fixed in stone.

But I would much prefer a van that size 7.95m long to have T/A's.
Just for interest what's your tyre pressures?

Hi Frenchchuffed, the pressure for the tyres is 65ilb

 

[Gagakev]

Raywood said;

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room.

Hi Raywood my van a Fleetwood is 7.95m long with an internal measurement of 6.7m with MTPLM of 1700kg
and it's a single axle. So not necessarily fixed in stone.

But I would much prefer a van that size 7.95m long to have T/A's.
Just for interest what's your tyre pressures?

Hi FrenchChuffed . Just as a point in passing. My Twin Axle 2001 Elddis Crusader SuperSirocco has a shipping length of 7.876mtrs.
It has an MTPLM of 1750kgs and a published MiRO of 1426kgs.
It runs on 175/65SR tyres with a recommended tyre pressure of 35psi albeit I have found that 38psi to be preferable.

The longer shipping length of the Fleetwood when compared to my SuperSirocco is most likely down to a longer 'A' frame that was often what Fleetwood were known for. It gives a more stable towing experience - I had a 1992 Fleetwood Colchester 1850 and it towed as straight as an arrow albeit a trifle heavy on the nose when empty and until balanced to my required 75kgs.

Hi TR have to agree about the stability with the longer A frame the measurement from the front of the hitch to the locker is 1200cm so thinking about it the internal measurement I gave of 6.7m would be reduced by the width of the front locker, so at a guess would be approx 30cm shorter inside.

 

[TheTravellingRooster]

Raywood said;

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room.

Hi Raywood my van a Fleetwood is 7.95m long with an internal measurement of 6.7m with MTPLM of 1700kg
and it's a single axle. So not necessarily fixed in stone.

But I would much prefer a van that size 7.95m long to have T/A's.
Just for interest what's your tyre pressures?

Hi FrenchChuffed . Just as a point in passing. My Twin Axle 2001 Elddis Crusader SuperSirocco has a shipping length of 7.876mtrs.
It has an MTPLM of 1750kgs and a published MiRO of 1426kgs.
It runs on 175/65SR tyres with a recommended tyre pressure of 35psi albeit I have found that 38psi to be preferable.

The longer shipping length of the Fleetwood when compared to my SuperSirocco is most likely down to a longer 'A' frame that was often what Fleetwood were known for. It gives a more stable towing experience - I had a 1992 Fleetwood Colchester 1850 and it towed as straight as an arrow albeit a trifle heavy on the nose when empty and until balanced to my required 75kgs.

Hi TR have to agree about the stability with the longer A frame the measurement from the front of the hitch to the locker is 1200cm so thinking about it the internal measurement I gave of 6.7m would be reduced by the width of the front locker, so at a guess would be approx 30cm shorter inside.

Hi again Gagakev. Yes - talking of long 'A' frames. Did you ever look at the Eterniti range and especially the IB4.
Now they were an 'A' frame and a half !!!

 

[Gagakev]

Raywood said;

To me the main advantage of a twin axle would be that it allows for a larger body so there is more room.

Hi Raywood my van a Fleetwood is 7.95m long with an internal measurement of 6.7m with MTPLM of 1700kg
and it's a single axle. So not necessarily fixed in stone.

But I would much prefer a van that size 7.95m long to have T/A's.
Just for interest what's your tyre pressures?

Hi FrenchChuffed . Just as a point in passing. My Twin Axle 2001 Elddis Crusader SuperSirocco has a shipping length of 7.876mtrs.
It has an MTPLM of 1750kgs and a published MiRO of 1426kgs.
It runs on 175/65SR tyres with a recommended tyre pressure of 35psi albeit I have found that 38psi to be preferable.

The longer shipping length of the Fleetwood when compared to my SuperSirocco is most likely down to a longer 'A' frame that was often what Fleetwood were known for. It gives a more stable towing experience - I had a 1992 Fleetwood Colchester 1850 and it towed as straight as an arrow albeit a trifle heavy on the nose when empty and until balanced to my required 75kgs.

Hi TR have to agree about the stability with the longer A frame the measurement from the front of the hitch to the locker is 1200cm so thinking about it the internal measurement I gave of 6.7m would be reduced by the width of the front locker, so at a guess would be approx 30cm shorter inside.

Hi again Gagakev. Yes - talking of long 'A' frames. Did you ever look at the Eterniti range and especially the IB4.
Now they were an 'A' frame and a half !!!

Saw the Eterniti at the NEC didn't take any noticeof the A Frame..... saw the price and walked on by!!!!

 

[FrenchChuffed]

Just as a footnote, as this issue will probably never be resolved without extensive testing. It would appear that the larger single axeled vans have a type pressure approximately 75% higher than an equivalent twin axel, so tyre maintenance and inspection and renewal becomes far more important. Safe caravanning Guy’s

Devils advocate, I just got a SA van and a tyre pressure monitor.