Audi A4 Avant 40 TFSI

[Odin]

This is my first post in this forum (actually, the second; the first one was to introduce myself...), so apologise if the topic has already been discussed. I have been researching and I couldn't find anything anyway.
I drive a company so that means that I change the car quite often. For this reason, and even if I have been towing only for three years, I have done so with a number of different cars: Nissan Qashqai (several models but mainly the Tekna 1.6 DCI 130 hp 4x4), XTrail 2.0, Audi A6 2.0 190 Quattro, VW Tiguan SEL 2.0 190hp 4Drive, Seat Alhambra 2.0 150 hp, and the latest one is an Audi A4 Avant TFSI 2.0 190 hp, front wheel drive. With both Audi (A6 and A4), I have towed only short distances, less than 100 miles. My caravan is a Sprite Major 6 from 2016, with a MRO of 1227 kg and MTPLM of 1445kg. We travel quite "light", without awning, chairs, table, bikes etc... so I reckon that the actual weight of the caravan should be around 1300 - 1320 kg. Not trying to sound pedantic, but I need to give this information to paint the whole picture
A couple of weeks ago we went to spend a week in Kent, and while driving down the M6, I started to overtake a lorry which was driving at around 50mph (I was doing 60). Everything was ok but suddenly, in the middle of the manoeuvre, the caravan began to sway, so I lifted the foot off a bit but it kept swaying quite heavily to the point that I switched on the emergency lights, expecting the jack-knife which fortunately didn't happen. It has been the closest I have been to this and it is not nice at all!. From that point I decided to go slightly below 60, and the rest of the journey was ok.
On the way back, traffic was much quiet, and for many miles I barely see other vehicles. At some point I saw a car transport lorry ahead, so I approached it with the intention to overtake it (again, driving at 60 mph). As I got closer to the lorry, I felt that the caravan started to sway again, not that badly but more than what it was comfortable. I overtook it and everything went calm again. I didn't have any other "incident".
I have been trying to think why it has happened. The kerb weight of the car is around 1600kg so a 85% match is 1360, which is less than I was towing. In addition, I have towed a lot with the Qashqai in the past and I've never had that issue. The day wasn't particularly windy and no other vehicle was overtaking me, and the issue on the way back was even more strange, as there was no traffic at all at that time.
The reasons that I can think of are:
A) The length between the rear axle and the towbar, which is longer than in most cars I have towed with
B) The height of the car, which is much lower than the other cars, and maybe the air affects the caravan more than with taller cars. I haven't found anything in this regards, though.
C) The nose weight limit relatively low of the A4 (80 kg), although I haven't exceeded it (not even closer...)
D) The front wheel drive (this and the Alhambra are the only non 4x4 that I have used for towing so far)
E) The relative light weight of the car, but the Qashqai is even lighter and I have never experienced anything similar.
F) A combination of all the above, plus maybe something else that I'm missing...
Thankfully I'm changing the car for a Q5 quite soon, as now I don't feel comfortable at all with this one.
Any advice, comment, etc will be most welcome, though. I would really like to understand as much as possible about the dynamics involved on towing a caravan!
Thanks all!
Alejandro

 

[Clifford_374377114]

My view is that your nosewight is too low. I suggest you get it as close to 80 kg as you can.
Cliff

 

[Craigyoung]

Plus the tow car you have seems fine , all your previous ones all seemed like they have been decent tow cars but still we have just travelled 2ooo miles returned journey from France & the most thing I dread is overtaking wagons especially car transporter ones it's just as you seem to get past the end of them & you get sucked in .

Its got nowt to do with it being 2 wheel drive or 4 wheel drive makes no difference , ours is only to 2WD and is fine .

 

[otherclive]

You say that you travel light but with battery, mover gas bottle(s) and a few other bits do you actually know the weight of your caravan? Have you put it on a weighbridge?

Some caravans (mine inc) when unloaded or relatively light are nose heavy so had you been placing weight at the back to get the noseweight down? Do car tyre perseus need adjusting for towing. My Superb's go from 210/220 (f/r) to 240/290 when laden and towing.

As Craig says car transporters are bad news, they create a great deal of turbulence. My advice would be to weigh the van in its normal loaded trim and make sure your noseweight
is near to the max allowed for the car.

 

[Craigyoung]

Same here like clive , my rear tyres go from 38 to 42 psi for towing .

 

[Parksy]

Other members beat me to it, noseweight needs to be as close to your limit as possible, tyre pressures on car and caravan need to be checked and another tip would be to try to plan overtaking manoeuvres, especially when large vehicles are being overtaken, when travelling up motorway inclines rather than when going downhill.

 

[Craigyoung]

Other members beat me to it, noseweight needs to be as close to your limit as possible, tyre pressures on car and caravan need to be checked and another tip would be to try to plan overtaking manoeuvres, especially when large vehicles are being overtaken, when travelling up motorway inclines rather than when going downhill.

I Parksy ,
if you're not fast you're last

Good point about over taking , no ; never do a downhill pass , I always do mine on the uphill when the wagons are slowing & struggling to about 55mph and you can power past but carefully .

 

[Odin]

Thanks all, very good advices here!
I will weight the caravan in travel conditions. As for tyres, yes mine needs to go up when towing, but I always check them, both car and caravan, before setting off.
As for the tow bar weight, this is a very good point. My current car is the one with lower nose weight limit so when I moved a couple of items from the front box of the caravan to inside the caravan (ahead or on the axle). Maybe I have reduced it too much so I will check this out.
I didn't know about car transporters, but thinking about it, it make sense that they disturb the air more than other transports...
As for overtaking downhill, definitely a no-no! Thanks Parsky for the advice!
So, does anybody think that the aerodynamics have something to do? I read in other forums that taller cars will reduce the impact of airflow to the front of the caravan and will help on creating a more laminar flow. Having said that, with the long distance between the back of the car and the front of the caravan, and the massive turbulences that this must generate, I have serious doubts about it. In aeroplane, for example, you just need a tiny plate in the leading edge, by the wing root, to break the laminar flow and create a controlled stall, so 4 feet of gap must be more than enough to create massive turbulences...

 

[otherclive]

Thanks all, very good advices here!
I will weight the caravan in travel conditions. As for tyres, yes mine needs to go up when towing, but I always check them, both car and caravan, before setting off.
As for the tow bar weight, this is a very good point. My current car is the one with lower nose weight limit so when I moved a couple of items from the front box of the caravan to inside the caravan (ahead or on the axle). Maybe I have reduced it too much so I will check this out.
I didn't know about car transporters, but thinking about it, it make sense that they disturb the air more than other transports...
As for overtaking downhill, definitely a no-no! Thanks Parsky for the advice!
So, does anybody think that the aerodynamics have something to do? I read in other forums that taller cars will reduce the impact of airflow to the front of the caravan and will help on creating a more laminar flow. Having said that, with the long distance between the back of the car and the front of the caravan, and the massive turbulences that this must generate, I have serious doubts about it. In aeroplane, for example, you just need a tiny plate in the leading edge, by the wing root, to break the laminar flow and create a controlled stall, so 4 feet of gap must be more than enough to create massive turbulences...

You make some valid points about airflow. I don't think it makes for that much difference as my Superb estate is lower than any car Ive had for years and is stable. In fact a lower car may be an advantage given it will be stiffer sideways that a higher riding SUV. Putting a roof box on my Superb makes little difference to the outfits behaviour. But generally the A4s seem to have good reputation as tow cars. I suspect its down to a subtle combination of load distribution, and noseweight.
In France many autoroutes place speed restrictions and caravans and trailers when going downhill.

I tend to find that these days there are so many large HGVs on motorways and mostly they have no problem travelling at governed speed that I dont bother to overtake as invariably there's another half dozen in front of the one you have overtaken away. Good luck in your sorting it out.

 

[Parksy]

It's significant that the instability both time happened during an overtaking manoeuvre so perhaps the turbulence between the car and caravan coupled with the buffeting turbulence from the truck has a bearing on this.
I've heard of a few instances of instability involving new caravans which are carrying no payload apart from a battery and gas bottle, so close to the limit noseweight is key on a lighter outfit.

 

[Odin]

Thanks otherClive, probably you are right: it must be a combination of less than perfect weight distribution and loads of HGV on the road. The trip was on Friday 23rd of August, and 8.4 million vehicles were expected on the roads for that day. It took me 6 hours to get from Nantwich to Maidstone!
I will look at weight, nose weight and distribution and I will give it a try down the M6...
One question for you, if you don't mind asking: what model of Superb do you have and what is your caravan? I really like this car and it could be a future option, so I would be interested to know a bit about it.

 

[Odin]

Thanks Parsky. Definitely I need to review the nose weight, and weight in general...

 

[otherclive]

Thanks otherClive, probably you are right: it must be a combination of less than perfect weight distribution and loads of HGV on the road. The trip was on Friday 23rd of August, and 8.4 million vehicles were expected on the roads for that day. It took me 6 hours to get from Nantwich to Maidstone!
I will look at weight, nose weight and distribution and I will give it a try down the M6...
One question for you, if you don't mind asking: what model of Superb do you have and what is your caravan? I really like this car and it could be a future option, so I would be interested to know a bit about it.

64 plate Superb 4x4 Estate with 170 ps engine and 6 speed DSG. I like it both as a solo car and Towcar. The van is only 1300 kg MTPLM but the engine has so much torque that I’d be quite happy going up to a 1400 kg van. Fuel consumption towing on long trips 30 mpg. Solo 50-55 although in Scotland 60 mpg was seen Stirling to Inverness.

Previously I had a 2010 XC70 D5 AWD and the Superb knocks it for six. The Volvo was a nice car but wallowed. It was not anywhere near as economical and the rear leg space was minimal. I’m 6 ft 4 in and don’t have the Superb seat full back and I can sit behind the driver seat without touching it. Even my wife at 5 ft 3 in complained about the Volvo. Superb also has enormous boot space too. Lastly I like the fact that it’s rear seat bases flip forwards. So caravan stuff can sit low down in the center of the car. Or the dogs can be harnessed there. Even with Disco, Sorento, Pajero in the past I’ve never had so much flexibility. So much in fact it causes indecision. Oh and cheap servicing too.

PS and full size spare too.

 

[Odin]

Thanks otherclive, I'll definitely shorlist it!

 

[Beachball]

Thanks otherClive, probably you are right: it must be a combination of less than perfect weight distribution and loads of HGV on the road. The trip was on Friday 23rd of August, and 8.4 million vehicles were expected on the roads for that day. It took me 6 hours to get from Nantwich to Maidstone!
I will look at weight, nose weight and distribution and I will give it a try down the M6...
One question for you, if you don't mind asking: what model of Superb do you have and what is your caravan? I really like this car and it could be a future option, so I would be interested to know a bit about it.

64 plate Superb 4x4 Estate with 170 ps engine and 6 speed DSG. I like it both as a solo car and Towcar. The van is only 1300 kg MTPLM but the engine has so much torque that I’d be quite happy going up to a 1400 kg van. Fuel consumption towing on long trips 30 mpg. Solo 50-55 although in Scotland 60 mpg was seen Stirling to Inverness.

Previously I had a 2010 XC70 D5 AWD and the Superb knocks it for six. The Volvo was a nice car but wallowed. It was not anywhere near as economical and the rear leg space was minimal. I’m 6 ft 4 in and don’t have the Superb seat full back and I can sit behind the driver seat without touching it. Even my wife at 5 ft 3 in complained about the Volvo. Superb also has enormous boot space too. Lastly I like the fact that it’s rear seat bases flip forwards. So caravan stuff can sit low down in the center of the car. Or the dogs can be harnessed there. Even with Disco, Sorento, Pajero in the past I’ve never had so much flexibility. So much in fact it causes indecision. Oh and cheap servicing too.

PS and full size spare too.

Also i like the Superb but it to low for me so i got the
Volkswagen Tiguan 2.0 SEL DSG 4Motion 190 ps its great

 

[Odin]

Also i like the Superb but it to low for me so i got the
Volkswagen Tiguan 2.0 SEL DSG 4Motion 190 ps its great

Fully agree, in fact this has been the best one I have had so far.

 

[ProfJohnL]

....
A) The length between the rear axle and the towbar, which is longer than in most cars I have towed with

B) The height of the car, which is much lower than the other cars, and maybe the air affects the caravan more than with taller cars. I haven't found anything in this regards, though.

C) The nose weight limit relatively low of the A4 (80 kg), although I haven't exceeded it (not even closer...)

D) The front wheel drive (this and the Alhambra are the only non 4x4 that I have used for towing so far)

E) The relative light weight of the car, but the Qashqai is even lighter and I have never experienced anything similar.

F) A combination of all the above, plus maybe something else that I'm missing...
Thankfully I'm changing the car for a Q5 quite soon, as now I don't feel comfortable at all with this one.

Any advice, comment, etc will be most welcome, though. I would really like to understand as much as possible about the dynamics involved on towing a caravan!
Thanks all!
Alejandro

Hello Alejandro
Towing handling is never an easy thing to predict, give the same outfit to two people and they can come back with entirely different opinions, but you have obviously thought about it and possibly identified some of the factors that can make a difference.

Your first point about the tow vehicles overhang is certainly a factor as it obviously adds lever length for the loads working on the rear axle. Any softness in the suspension in any direction will be exploited and may produce a tendency for instability.

The height of the tow vehicle will affect the air flow around the caravan, But exactly how is a very complex issue. As with all aerodynamics, particularly at high speeds a small mechanical difference can sometimes make a big aero difference. But whether height of tow vehicle consistently improves or deteriorate a towing experience is open to a lot of speculation unless someone has a aero modeling software package and a super computer to run it on.

The EU regs require car manufacturers to have a minimum noseload capacity of 25kg or 4% of the cars rated towed weight limit. This suggests a noseload limit of 80kg gives rise to a towed weight suggests the car has a towed weight limit of 2000kg. So the Audi has a healthy nose load limit for the size of vehicle.

Most caravanners never need the capabilities of a 4x4 drive system, Fwd is a perfectly adequate format and should not affect the towing capability on normal roads. If the addition of a caravan's noseload upsets the cars level of traction, then it's most likely the trailers nose load is way too high, or the cars boot is over loaded.

The weight of the car is certainly a factor, and it is better to have the heaviest that's meets your requirements.

These are all factors and it's almost impossible to put your experience down to just one of them, but equally the driver is also a key component in the matter, the driver controls the loading, the maintenance, speed and braking etc..

 

[xtrailman]

My view is that your nosewight is too low. I suggest you get it as close to 80 kg as you can.
Cliff

This would be my advice, along with driving slower, i would also avoid overtaking a car transporter if practical.

 

[xtrailman]

Thanks otherClive, probably you are right: it must be a combination of less than perfect weight distribution and loads of HGV on the road. The trip was on Friday 23rd of August, and 8.4 million vehicles were expected on the roads for that day. It took me 6 hours to get from Nantwich to Maidstone!
I will look at weight, nose weight and distribution and I will give it a try down the M6...
One question for you, if you don't mind asking: what model of Superb do you have and what is your caravan? I really like this car and it could be a future option, so I would be interested to know a bit about it.

64 plate Superb 4x4 Estate with 170 ps engine and 6 speed DSG. I like it both as a solo car and Towcar. The van is only 1300 kg MTPLM but the engine has so much torque that I’d be quite happy going up to a 1400 kg van. Fuel consumption towing on long trips 30 mpg. Solo 50-55 although in Scotland 60 mpg was seen Stirling to Inverness.

Previously I had a 2010 XC70 D5 AWD and the Superb knocks it for six. The Volvo was a nice car but wallowed. It was not anywhere near as economical and the rear leg space was minimal. I’m 6 ft 4 in and don’t have the Superb seat full back and I can sit behind the driver seat without touching it. Even my wife at 5 ft 3 in complained about the Volvo. Superb also has enormous boot space too. Lastly I like the fact that it’s rear seat bases flip forwards. So caravan stuff can sit low down in the center of the car. Or the dogs can be harnessed there. Even with Disco, Sorento, Pajero in the past I’ve never had so much flexibility. So much in fact it causes indecision. Oh and cheap servicing too.

PS and full size spare too.

Also i like the Superb but it to low for me so i got the
Volkswagen Tiguan 2.0 SEL DSG 4Motion 190 ps its great

I have the same car a 2019 model with factory towbar,, its ok but no where near as good at towing as the 175cx5 i had.