thalls01 wrote:

---

Hi, I write to enlist the advice of others that have experienced caravan sway and worked to eradicate it.

I have owned many caravans previously and have never experienced sway like that in the new van we purchased late in 2021.

I was on the North-South Highway travelling back from McLaren Vale.  I entered a rise followed by a small passage downhill before a steeper hill the other side when a Quarry Truck pulling a trailer overtook me.  I was doing 85km/h at the time.

I was aware of the pressure wave trucks create as they pass you but were not ready for the mild sway this caused, lasting up to 45 secs - more than anything I had experienced in the past.  I kept a cool head and accelerated as I entered the hill in order to pull the caravan into a st. line.  Even so, it was unnerving and had me thinking what if it had been a road train on a smaller country road with undulations or even camber.  On arrival home I set about corrective actions to overcome the issue.

I researched the vehicle's and caravan's tyre pressures to ensure they were close to that specified.  They were; and were not a factor.

The ball weight of the 21' caravan was 140kg at Tare and 190kg loaded, the latter as measured by me using a ball weight scale.  I took before and after measurements of the rear and front of the Ford Everest - unloaded and loaded hitched to the fully laden caravan to arrive at the 190kg ball weight.  The rear of the Everest dipped by 47mm.  The obvious was that my front wheels were light on the ground.  I consulted various suspension companies and received mixed opinions - 'fit air bags to your rear springs', 'fit a weight distribution hitch' and 'replace the soft Everest springs with heavier duty springs, air bags and dampers'.

- I discounted the air bags only solution as correcting the sway sufficiently that I had experienced.

- I purchased a Fastway weight distribution hitch (WDH) 'Equalizer 2' with sway control but believe I have potentially reduced the caravan's ball weight by up to 30%, i.e. 133kgs.  This is a lot lighter than the AUS standard of the ideal ball weight being between 10-15% of the loaded caravan.  My calculations are that the van is 2800kgs loaded and that may be a tad generous (van's ATM is 3200kg).  I have also calculated that I have 400kgs allowance compared with the Everest's GCM (gross combined mass = caravan + car both loaded).

Now applying the lesser AUS standard of 10% that would suggest I should have a ball weight of 280kgs when fully loaded and hitched.  I have potentially 133kg to 148kgs.  This leads to the question below.

 

Q1.  Knowing that I never stow weights forward or aft of the caravan's axles to avoid the 'dumb-bell effect' of the rear and front of van swaying, how critical is it that I increase the van's ball weight?

I have spoken to my local Pedders distributorship this afternoon and new information has emerged.  The salesman claimed he had family members that owned Ford Everests with one pulling a Jayco van.  He stated the Everest's springs are very soft and ill-tolerant of towing vans - even with low ball weights.  He strongly recommended that I fit heavier duty springs, air bags and new dampers.  He stated in his brother's instance, that after doing so the Everest required only a little assistance from the air bags and the rear no longer sank by the margin with the Jayco van hitched.

I suspect the Pedders advice is correct since weak coil springs would offer poor resistance to caravan sway, and minor corrective action of the air bags for firmness is in accord with my understanding of the use for which air bags were intended.

I now fear I possibly have outlaid money on an 'E2' hitch for nothing.  The Pedders guy seemed to think it could be useful incorporating the hitch as well but it would not have to be tensioned as much.  This leads into my next question.

 

Q2.  Have other owners with a Ford Everest had their rear suspension altered as the Pedders guy has proposed for $1700?  (A reasonable amount of money but there again you cannot put a price on safety on the road.)

At the end of the day I wonder how necessary it is given I have the WDH & sway control in the E2 hitch.

PLEASE NOTE:  With the E2 hitch fitted the Ford Everest rear now dips 21mm with car + van loaded compared with 47mm without hitch.  The car and van are level and in the horizontal plane (no foreseeable problems).

 

 

Q3.  Bottomline: Given the facts shared above, should I proceed with Pedders to have my rear suspension upgraded OR leave my safety in the hands of the E2 WDH and Sway Control hitch?

 

FUTURE THOUGHTS/INTENTIONS - TO FACTOR IN

I have added a further 17kg to the A-frame of the caravan in a motorised jack since the above car measurements and ball weight of 90kg was taken.  I am also to potentially add a vertical bike rack for 2 bikes to the rear of the A-frame above the toolbox.  This will no doubt add additional ball weight, in which case the E2 WDH may still play a vital role in reducing ball weight and distributing that weight to the Everest's front wheels. 

All  thoughts/experiences of fellow members welcome.

---

Hi Timothy. Because I am presently working 15 hour days I can't give you the assistance you desperately need.,but you are being led up the garden path by the people you have spoken to. Their job is to sell you as much rubbish as they can, as theit income is often commission based. WHEN I get time I will assist, but a WDH DOES NOT change ball weight. EVER. The Everest is a great tow vehicle, and I have afriend who swears by his, but your ball weight is WAY too low for starters. Sorry I can't help at present, but I will get back to you as soon as I can. Just hold fire and don't waste even more money.Good luck! 

REMARK: Just noticed a typo in relation to the loaded ball weight in my summing-up of original post, as below.  

"FUTURE THOUGHTS/INTENTIONS - TO FACTOR IN

I have added a further 17kg to the A-frame of the caravan in a motorised jack since the above car measurements and ball weight of 90kg (SHOULD BE 190KG) was taken."  190kg ball weight was the loaded ball weight of caravan.

 

Hi Bicycle camper,

You are echoing yobarr's comments regarding the caravan's plated ball weight being too light at 140kgs, and I thank-you for your opinion.  'Yes', I agree with you, with my ball weight as it is, I couldn't hope to do the road limit of 100km/h without a large mishap I expect.

Can I ask what the Tare (plated) ball weight should be for a caravan with an internal measurement of 21 feet before the A-frame? I have had it said to me that it should be 220kgs and above. Would that be correct?

I need further expert advice before I can address this with the dealership that sold me the van.

SA Grey Nomad members, are you aware of a company that can provide expert/definitive advice on (i) the ideal range of plated ball weight at Tare for a 21' van, and (ii) what I can do to increase this ball weight??

If indeed, the plated (Tare) ball weight needs to be increased, it would see the obvious correction to increase ball weight would be to move one of the 2 x 85 Litre drinking water tanks (with low gravity) forward towards the A-bar.  These are currently in front of the first axle to the front of the van but inspecting underneath yesterday, thee is room for one/both to be moved further forward.  Would you agree?

I hope the dealership and manufacturer concede they got it wrong and are prepared to do the necessary correction/s the van's ball weight without going legal.

It really sucks purchasing a new van to learn the van mass - ball weight ration is poorly matched contributing to sway.  It is even more difficult to get accurate, expert advice from suspension companies out there without potentially being taken for a ride.

This is why I have resorted to this forum.

All qualified opinions welcome - Tim 

Different tyre pressures front and rear of the caravan could help

thegreynomads.activeboard.com/t67078068/tandem-axle-different-tyre-pressures-front-and-rear/

'Are We Lost', firstly thanks for the great advice.

I respond for you and others below.

Per "Towball scales are notoriously inaccurate. When you say you "took before and after measurements of the rear and front of the Ford Everest ..... to arrive at the 190kg ball weight" do you mean with a tape measure, or over a weighbridge? The only satisfactory way is at a weighbridge."

I confirm I took the loaded van (2800kg) ball weight with a set of towball scales on level ground. "Yes", I did understand that towball scales can have a reasonable margin of error.  I take your point of taking the tug and caravan to a weighbridge to definitively establish the GCM and caravan's ball weight with both vehicles loaded.

In terms of the rear and front measurements taken of the Everest, these were taken when (i) fully unloaded (no caravan hitched), (ii) loaded with caravan hitched (no WDH) and (iii) loaded with WDH and Caravan Hitched. I provide these measurements below for completeness. I advise the car appeared level in the unloaded condition with no sagging of the rear on a flat horizontal plane.

1) EVEREST UNLOADED

FRONT: 920mm
REAR: 939mm

2) EVEREST LOADED (Car & Caravan with Payload) and Hitched to Caravan (NO WDH)

FRONT: 937m
REAR: 892mm
*Ball Weight (download) as measured using Ball Weight Scale: 190kg  (Plated Ball Weight of Caravan at Tare: 140kg)


EVEREST FRONT MEASUREMENTS (Before & After) - NO WDH
Unloaded:  920mm
Loaded, with Caravan Hitched: 937mm (nosing upward).

I.E. A difference of 17mm in height with Caravan hitched.


REAR MEASUREMENT (Before & After) - NO WDH
Unloaded:  939mm
Loaded, with Caravan Hitched: 892mm

I.E. A difference of 47mm (almost 2 inches lower) with Caravan hitched.


WITH FASTWAY 2E HITCH INSTALLED - ARGUABLY OVER-ADJUSTED (I have dropped spring bars one setting to compensate since).
Front: 915mm
Rear: 918mm

It would be valuable if someone could point me to the measurements to take at the weighbridge, either a link or pasting the procedure in this post.

In answer to your question per weight in the Everest with payload, I calculated that as 2650kg with our payload placed immediately behind the back seat and secured.  The payload consisted of tools, a HD air compressor, ropes, rags, spade and a single tyre recovery track - potentially 50kgs.  Per persons in the car, just my wife and me, lol.

Hope this helps you and others to further assess what further corrective actions (if any) I should take.

I will report back on this forum my findings from attending the public weighbridge.  As  I say, advice of the procedure/measurements to obtain at the weighbridge would be helpful prior.

Cheers, Tim 

As suggested by Peter, you may well improve things with tyre pressures on the van. Probably more important in my view are the Everest tyre pressures. You said all tyre pressures were set to specifications. I like to feel the tyres for similar temperatures when stopping after some highway travel. I use it as a rudimentary check for a slow leak, but it will also highlight if one axle or tyre is getting more load than the others. My Ranger rear tyres get warmer than I would like but they are already inflated to the maximum psi as stamped on the tyres.

Also, adding to my earlier post, your comment about the WDH reducing the ball weight does not seem valid. Once connected, you can not measure ball weight. Are you referring to reduced rear axle load on the Everest? That is what a WDH is designed to do. A ball weight of 190kg translates to a rear axle increase of around 150% of that due to leverage (varies depending on the distance the ball is behind the rear axle). So that 190kg means increasing the rear axle load by around 300kg. This change is one of the before/after measurements that needs to be taken at the weighbridge. A WDH should initially be adjusted to transfer about 150kg of that weight back to the front wheels. A small proportion (20kg?) would be added to the van wheels.

-- Edited by Are We Lost on Saturday 19th of March 2022 01:25:40 PM

'Are We Lost' - thanks for the below advice.

"Also, adding to my earlier post, your comment about the WDH reducing the ball weight does not seem valid. Once connected, you can not measure ball weight. Are you referring to reduced rear axle load on the Everest? That is what a WDH is designed to do. A ball weight of 190kg translates to a rear axle increase of around 150% of that due to leverage (varies depending on the distance the ball is behind the rear axle). So that 190kg means increasing the rear axle load by around 300kg. This change is one of the before/after measurements that needs to be taken at the weighbridge. A WDH should initially be adjusted to transfer at least 150kg of that weight back to the front wheels. A small proportion (20kg?) would be added to the van wheels."

Just as a point of clarification, if I was to use the max pressure indicated on my Ford Everest tyres that would have me pump them to 80PSI all round. That seems a lot. My calculated ideal PSI for the rears is 43PSI and 41PSI for the FRONT using maths which account for payload, the tryre's rated load and loaded ball weight. I have 17" rims. Out of interest, what do you inflate yours to?

My comment per a WDH reducing the ball weight was a statement provided me by the caravan dealership's salesperson, himself an off-roader with experience. Clearly it was incorrect advice much to my relief having outlaid on a WDH. Thanks for your explanation of how the WDH works to transfer weight to the front wheels. I should have realised that on thinking about it since it is using the rear axle as a fulcrum. Which is why I take your point and that of others, I must check have the vehicle hitched to the caravan weighed at the weighbridge.

A question regarding the before and after measurement at the weighbridge, were you referring to the weight of the car with and without the WDH?? Could you specify a little more ...

Cheers, Tim

Many thanks 'Are we Lost' for the weighbridge procedure and your precious time. That all makes sense. I will now proceed with the weighbridge.

I was aware the 190kg is included in the Everest's weight but will check I did not oversight it in my calculations - thanks.

For the record I found the specs relating to the Everest's front and rear axles, as below.

o Maximum Front Axle Load : 1480kg
o Maximum Rear Axle Load : 1750kg

Surely with a low caravan ball weight and not more than 50kgs of payload in the car I am not over.


I will report back everyone with my findings from the weighbridge attendance - thanks to all concerned - very much appreciated - Tim

Hi Tim,

I went through a similar exercise a few years ago when looking for a vehicle and van to tow.  As a result, I built the spreadsheet I have attached which enabled me to compare vehicles and vans to ensure my combination was all legal.  The initial things you need to do is get all the empty weight values from a weighbridge, all the distances between load points using a tape measure and all the ratings for the vehicle and van.  The "Tugs and Vans" TAB in the spreadsheet has the headings you need to get values for.  I have already created a row for each of your vehicle and van but you will need to complete the missing detail.  I would also reconfirm your Tare and Kerb vehicle weights from the weighbridge.  Since you already have a towbar and possibly a bull bar, these can be included in your new Tare and Kerb weights as measured on the weighbridge.

Once you have all the initial values, the real fun starts on the "Load calculator" TAB.  There are 3 Options.  Option 1 assumes the vehicle is fully loaded and you can only play with the van loads, Option 2 assumes the van is fully loaded and you can only play with the vehicle loads and Option 3 allows you to play with both the vehicle and van loads to get the optimum setup.

The "Instructions" TAB on the spreadsheet should give you more info and each heading wihich has a small red triangle also gives advice when clicked on.

I have also attached a Tyre Pressure spreadsheet to assist.

I hope you get some value from this.

A 50kg washing machine removed from the back of the van would make a HUGE difference. Not just weight distribution, but to the pendulum effect when sway starts. Also, often that weight will not be included in the TARE.

I forgot to cover your point about 80 psi rating on the tyres. Assume you are loaded to the maximum rating for your rear axle at 1750kg. That is 875kg per tyre. Divide that by the tyre load rating to get the percentage of maximum you are running.

e.g if your tyres are load rated to 1250kg, then 875/1250 = 0.7 (or 70% of maximum rating). Apply the same ratio with max PSI and you get a target of 56psi. Use your own load rating to determine the target psi.

Use that as a starting point and check for 4 psi pressure rise once on the highway. A rudimentary indicator is to feel how the heat compares to the front. Adjust as necessary. You can use the same principle to validate the van tyre pressures.

 

Kevin J - thanks so much for your Excel spreadsheets.  Fortunately I am IT literate.  I have downloaded these and will give them a good lookover before attending the weighbridge tomorrow, Sunday 20/3, and will use them to assist my calculations.  Good to know that I am exploring a well-trodden path in terms of making my tug and caravan safe and legal.  Mind you, it has been an extended learning curve!!

- I will also see how they can incorporate the weighbridge routines outlined by 'Are We Lost' for which I am also very grateful for his multiple inputs and generous advice.

Watsea - your above advice regarding the caravan loaded ball weight being too light at 7% of the loaded weight - matches my thinking.  I may just have to move the washing machine form the rear of the van as 'yobarr' and 'oldbloke' seconded.  I will await the weighbridge results before taking this action.

In terms of the WDH, the mechanism at work in shifting weight from the Everest's rear axle to the front and also distributing some of this weight to the van's wheels via the A-frame all makes sense.  Thanks for the detailed explanation.

 

Tomorrow morning Grey Nomads will be a period of reckoning at the local weighbridge at Marion, SA.  I will post the raw results and also the results using KevinJ's Excel spreadsheet. 

Thanks to all who have contributed thus far.  I am blown away by all the generosity of persons on this forum - Tim 

  

 

 

 

 

 

From the manual for the Dometic washing machine I removed from the rear of my van .....

But as you say, it may well be a lot lighter.

 

Are We Lost wrote:

---

From the manual for the Dometic washing machine I removed from the rear of my van .....

But as you say, it may well be a lot lighter.

 

---

 

I wonder if that spec weight is when in operation with clothes, water in it. Interesting.

Here is the specs I found, there is a few brands and the specs are very similar.

When we brought our secondhand caravan I was going to take the washing machine out as I was concerned with excessive weight but on lifting it out I realised it was not that heavy not like our home machine.

 

 

 Model Size Weight Rated wash & spin load Rated Power Input

2.5kg - 041133 410 x 420 x 640mm 16kg 2.5kg (dry clothes) 235W max

3.0kg - 044131 410 x 420 x 740mm 18kg 3.0kg (dry clothes) 1035W max

2.5 & 3kg models

Rated Voltage 240V~ Rated Frequency 50Hz

Maximum water pressure Minimum water pressure 

permitted @ water inlet permitted @ water inlet 

KevinJ - I have just compared your tyre spreadsheet with my calculations. Came out spot on. Did wonder how to enter KPA until I noted your conversion table beneath. Very straight forward - thanks. Look forward to using after weighbridge when actual loads calculated.

Are We Lost - will try and obtain all 8 measurements at weighbridge for accuracy.

KevinJ - looked at your Load Spreadsheet Calculator. That actually blew my mind away - so comprehensive and thanks for setting my Everest and Diamantina up. It is clear you are an Advanced Excel operator. I was once and have looked at your formulae - well done. I may have to come back to you with questions but wow there isn't much you have not taken into account - even down to inclusion of the fridge thermometer!! I look forward to inserting the weighbridge figures in the tables but may possibly need to forward spreadsheet back to you for your thoughts/oversight. A post ago I attempted to include a picture of the suspension underside of van. I am not confident I went about the insertion procedure correct. I am guessing the only way to know is to post to test that the link worked.

Cheers all - Tim