Wallowing Ride with Ford Kuga 2019 and Elddis Xplore 524

[LateGuitarist]

I have the 2.0 Tdci 180hp (Vignale) model with which I tow an Xplore 524, which is seldom particularly laden, in fact most of the time I don't even have anything other than a small 12V battery for emergency purposes such as starting the fridge, and one 6kg and a 4Kg standby gas bottle. Tyre pressures are always maintained at the correct value as recommended. Problem I have is quite a "wallowy" ride when car is lightly loaded and 2 people on board, for example when going away for just a few days, no awning or other paraphernalia. When fully laded with 4 adults, awning, luggage etc etc it is way better. Van has always been dead level when hitched up, towbar has no means of adjustment as it's an automatic factory fitted one. The ride is stable it's just the up and down oscillation that is a bit uncomfortable on uneven, generally smaller roads.
Wondering if anyone has had a similar problem and fitted anything to stiffen things up? Not sure if there are stiffer aftermarket rear springs but this would probably make the car quite uncomfortable when solo unless there are any adjustable options available? To be honest the car is a bit soft suspension wise at the best of times even solo so might not be too bad if springs were uprated? Any idea's (apart from changing car of course!)?

 

[RogerL]

First thing to check is the caravan noseweight - too light or too heavy can cause wallowing - the industry "recommends" 5-7% of MTPLM but the 7% is often because the caravan hitch is itself limited to 100 kg. In my opinion, the heavier the noseweight the better BUT you MUSTN'T exceed the limit of the caravan hitch or the car's noseweight limit.

MAD auxilliary springs may be available for your car but you will need to inform your insurer of the modification and some won't accept it. I used MAD springs on a 2000 Astra which wallowed, it cured it and still handled fine when solo.

 

[ProfJohnL]

.... Van has always been dead level when hitched up, towbar has no means of adjustment as it's an automatic factory fitted one.

That will simply depend on the height of the cars hitch, and the height of the caravans hitch but it is affected by how much nose load you have trimmed the caravans too. But there is absolutely no particular advantage to trimming the caravan to tow level.

I have just seen that Roger has posted the recommended nose load range.

Car manufacturers these days spend a lot of time and money to establish the correct design and specification for suspension and tyres for each model they produce. The regulations they have to follow will ensure the car will maintain adequate composure and control for all the loads the car is rated for, thus there should never be a need to consider fitting uprated or spring assisters.

Don't forget that many vehicle specifications set higher tyre pressures when towing.

If you feel assistors may be needed, then the first thing you should do is to verify if the vehicle is actually being over loaded, and if it is then you must bring the load within specification.

Secondly if the load is within the vehicles specifications, and you still feel its too soft, then you need verify that your cars suspension and tyres are not worn or damaged.

If you still think the suspension is too soft, then I suggest your desire to uprate the springs is not not based on sound technical thinking, and you need to modify your desires.

There is another reason why changing spring rates particularly on modern cars is a bad idea. Many car to day employ stability control systems, which rely on various sensors around the vehicle feeding information to a computer that monitors body motions and other dynamic characteristics. If you change the suspensions characteristics, the wrong information will be sent to the stability control system which may cause it to apply the wrong interventions actually creating an adverse correctection.

As has already been suggested changing spring rates is a modification, and you need to advise your insurer, who might decline to continue to cover the vehicle.

If you really want a stiffer suspension you only realistic solution is to consider changing your tow vehicle.

 

[otherclive]

I'm surprised that with a short overhang the Kuga isn't okay for you. I won't repeat the advice above, but I've had three cars where I had to change the rear suspension. I had Saab 9000 which had a long overhang and installed MAD auxiliary springs which sit inside the OEM coil springs. Did the same on a 2014 Superb estate again with long overhang. In both cases the ride height unloaded increased slightly as the auxialiary springs required a bit of preload so as not to rattle around when the car was lightly loaded. On both cars there was no noticeable difference to driving charachertsisic when solo but when loaded and towing there was an imprrovment.

The third car I modified was a 2014 Subaru Forester XT which suffered a broken rear offside spring. On that car there is little overhang but the springs work in conjunction with the dampers which have a small hydraulic "pump" that as the car moves the 'pump" pressures the damper to maintain self levelling road height. This means the damper takes some of the load which the spring shares. Post Covid springs were not available from Subaru so I fitted a set of coils over spring dampers from an Australian company, Pedders. I'd used their kit before on an off roader. What I fitted did away with self levelling and the spring took full load and the damper damped. The ride height increased a bit as the car had done 50K miles, but it drove far better solo and towed very well. The lack of self levelling wasn't noticeable and the HID headlights took their input from elsewhere on the susleniosn so I didn't dazzle oncoming traffic.

For all three instances I notified the insurers who just noted the modifications and it made no effect on premiums.

 

[LateGuitarist]

That will simply depend on the height of the cars hitch, and the height of the caravans hitch but it is affected by how much nose load you have trimmed the caravans too. But there is absolutely no particular advantage to trimming the caravan to tow level.

I have just seen that Roger has posted the recommended nose load range.

Car manufacturers these days spend a lot of time and money to establish the correct design and specification for suspension and tyres for each model they produce. The regulations they have to follow will ensure the car will maintain adequate composure and control for all the loads the car is rated for, thus there should never be a need to consider fitting uprated or spring assisters.

Don't forget that many vehicle specifications set higher tyre pressures when towing.

If you feel assistors may be needed, then the first thing you should do is to verify if the vehicle is actually being over loaded, and if it is then you must bring the load within specification.

Secondly if the load is within the vehicles specifications, and you still feel its too soft, then you need verify that your cars suspension and tyres are not worn or damaged.

If you still think the suspension is too soft, then I suggest your desire to uprate the springs is not not based on sound technical thinking, and you need to modify your desires.

There is another reason why changing spring rates particularly on modern cars is a bad idea. Many car to day employ stability control systems, which rely on various sensors around the vehicle feeding information to a computer that monitors body motions and other dynamic characteristics. If you change the suspensions characteristics, the wrong information will be sent to the stability control system which may cause it to apply the wrong interventions actually creating an adverse correctection.

As has already been suggested changing spring rates is a modification, and you need to advise your insurer, who might decline to continue to cover the vehicle.

If you really want a stiffer suspension you only realistic solution is to consider changing your tow vehicle.

Absolutely agree with your comments regarding modifying the original suspension. As I mentioned the problem is much less when more fully loaded, to be honest we don't tend to take much "stuff" with us most of the time and the Van is usually pretty lightly loaded, there is no chance it is anywhere near it's Max towable mass. I think I might have took my eye off the ball a bit despite having been caravanning for 3 decades, probably worth getting a nose weight scale and looking a bit more scientifically at things particularly as the Van has a big locker rear of the axle in which are placed a table, chairs, hook up and other bits and bobs that may be lightening the nose too much, given the small battery I use. Also the fixed bed is rear of the axle. probably need to start putting more stuff forward of it.
A quick look underneath the car confirms your comments regarding sensors etc!
Thanks for your wise words, probably spent too much time fixing the leaky front window!! (worked though)

 

[LateGuitarist]

I'm surprised that with a short overhang the Kuga isn't okay for you. I won't repeat the advice above, but I've had three cars where I had to change the rear suspension. I had Saab 9000 which had a long overhang and installed MAD auxiliary springs which sit inside the OEM coil springs. Did the same on a 2014 Superb estate again with long overhang. In both cases the ride height unloaded increased slightly as the auxialiary springs required a bit of preload so as not to rattle around when the car was lightly loaded. On both cars there was no noticeable difference to driving charachertsisic when solo but when loaded and towing there was an imprrovment.

The third car I modified was a 2014 Subaru Forester XT which suffered a broken rear offside spring. On that car there is little overhang but the springs work in conjunction with the dampers which have a small hydraulic "pump" that as the car moves the 'pump" pressures the damper to maintain self levelling road height. This means the damper takes some of the load which the spring shares. Post Covid springs were not available from Subaru so I fitted a set of coils over spring dampers from an Australian company, Pedders. I'd used their kit before on an off roader. What I fitted did away with self levelling and the spring took full load and the damper damped. The ride height increased a bit as the car had done 50K miles, but it drove far better solo and towed very well. The lack of self levelling wasn't noticeable and the HID headlights took their input from elsewhere on the susleniosn so I didn't dazzle oncoming traffic.

For all three instances I notified the insurers who just noted the modifications and it made no effect on premiums.

A quick look under the car has convinced me I am not going to start dismantling anything, need to undertake some weight distribution tests, which I should really have done anyway. Think I have fallen into the probably common familiarity trap after 30+ years caravanning! As you say it has a short overhang and when more fully loaded the problem was much reduced, thanks for your input.

 

[LateGuitarist]

First thing to check is the caravan noseweight - too light or too heavy can cause wallowing - the industry "recommends" 5-7% of MTPLM but the 7% is often because the caravan hitch is itself limited to 100 kg. In my opinion, the heavier the noseweight the better BUT you MUSTN'T exceed the limit of the caravan hitch or the car's noseweight limit.

MAD auxilliary springs may be available for your car but you will need to inform your insurer of the modification and some won't accept it. I used MAD springs on a 2000 Astra which wallowed, it cured it and still handled fine when solo.

Just ordering a nose weight scale.

 

[Hutch]

Fully agree with the others, maybe as you say, you might have just badly loaded the van, and need more nose weight.

I found that although on some roads the van towed very well, and then on others, we ended up after an hour thinking we had been on a boat.
The Profs favourite scales are bathroom scales 6 months worth of Practical caravan magazines and a lump of wood , works well.

 

[Buckman]

Just ordering a nose weight scale.

Which one have you ordered as Milenco and Reich seem to be the only ones that make a decent scale for the nose weight of the caravan.

 

[otherclive]

A quick look under the car has convinced me I am not going to start dismantling anything, need to undertake some weight distribution tests, which I should really have done anyway. Think I have fallen into the probably common familiarity trap after 30+ years caravanning! As you say it has a short overhang and when more fully loaded the problem was much reduced, thanks for your input.

I tended to find that my outfits were generally more jittery when low loaded. Be interested in hearing an update after you have changed a few things.

 

[LateGuitarist]

Which one have you ordered as Milenco and Reich seem to be the only ones that make a decent scale for the nose weight of the caravan.

Milenco

 

[LateGuitarist]

I tended to find that my outfits were generally more jittery when low loaded. Be interested in hearing an update after you have changed a few things.

Got the scales ordered, I'm off to Cornwall soon so I'll report back on findings before and after once I have determined what the NW actually is at the moment.

 

[LateGuitarist]

Well my shiny new Milenco scales arrived today, so I have just stuck them under the hitch, having left the van in more or less the same state as it was towed home in, nose weight is 65Kg. Given the MTPLM is 1325kg I am assuming that distributing weight forward of the axle to take it up to 7% (93Kg) or even 100Kg may well help relieve the problem? I have never really had any previous problems possibly more by luck having never had any scales before. Also just realised the spare 4KG gas bottle ran out on the last trip so that won't have been helping.
Any thoughts?

 

[otherclive]

Well my shiny new Milenco scales arrived today, so I have just stuck them under the hitch, having left the van in more or less the same state as it was towed home in, nose weight is 65Kg. Given the MTPLM is 1325kg I am assuming that distributing weight forward of the axle to take it up to 7% (93Kg) or even 100Kg may well help relieve the problem? I have never really had any previous problems possibly more by luck having never had any scales before. Also just realised the spare 4KG gas bottle ran out on the last trip so that won't have been helping.
Any thoughts?

What is the limit of your cars towball, that mustn’t be exceeded.

 

[LateGuitarist]

What is the limit of your cars towball, that mustn’t be exceeded.

100Kg according to vehicle handbook.