Tyre pressures - Swift Sundance 580PR

[Woodlander]

Sorry if this subject has been done to death but I've done a forum search in Motorhome Matters and Hints and Tips for "tyres" and "tyre pressures" and got zilch.

 

The handbook of my Swift Sundance 580PR tells me that the tyre pressure (front) should be 5BAR=72.5psi and (rear) should be 5.5BAR=79.7psi.

 

It is fitted with CP tyres and the GVW if 3500kg.

 

This pressure seems incredibly high. And it gives a pretty hard ride.

Is it right?

 

There seems to be some highly experienced and knowledgable gurus on this forum who might have an opinion.

[colin]

First step is to get the van weighed when fully loaded then you can calculate correct tyre pressures from online chart (I can't find link at moment) or contact tyre manufacturers who may give you corrected figures.

[Tracker]

If you contact the maker of the tyres and quote both axle weights fully loaded (courtesy of your local weighbridge) they should be able to advise, although some tyre makers are more helpful than others.

 

You don't say what year van or make or sizes of tyres it has and all of these are relevant?

 

It is very dodgy to alter tyre pressures without qualified advice - preferably written or at least emailed from the tyre makers because in the event of an accident the legal ramifications could be costly.

 

That said those pressures do seem a bit high to me too and would certainly not help the ride.

 

I believe your van may be on the standard Fiat commercial chassis (as opposed to a camper or Alko chassis with softer suspension) and as such will be a harder ride anyway

 

As an aside, the rear lounge layout of the 580PR is on our possibles list for a change - how do you like it - does the layout work well for you - any grumbles - or plaudits??

 

By the way it might be as well to hide your email address to avoid it being misused??

[Woodlander]

Thanks for that helpful advice.

We love our rear lounge Sundance - it was the reason we bought it last year after ordering it at the NEC.
It's really comfortable and just right for an afternoon snooze.

We don't make up the double bed. We use it as two singles and bought a couple of Duvelays.But because of the bulk of the Duvelays we just use the memory foam matresses which came with them and a sleeping bag.

The table is very badly sited and pretty heavy. You have to lift one of the lounge seats to get to it. So we did away with that and bought a lightweight table which we store behind the driver's seat padded with the Silver Screens! :->

There is plenty of storage and the water and waste tanks are easily accessible for cleaning/draining.

We went for the 130bhp upgrade and are glad of it.Averaging 27/28 mpg at the moment, but the engine is still a bit tight so it will probably improve.

Happy Hunting!!

[Tracker]

Thanks Graham - about as we suspected.

We too use Duvalys and one of the issues in almost any non fixed bed van is storing two bed rolls 25" wide and 17" in diameter as they take a heck of a lot of locker space and are all floppy when being moved!

Separating the memory foam topper from the bag occurred to me too but you still have to store both bits!

 

This link might help you find a weighbridge if you don't know of one near you as axle weights are crucial for calculating tyre pressures - or you could just take each maximum axle load as per the weight plate and hope for the best, but you might end up with overly high pressures as the sum of the two is greater than the total allowable weight to allow for uneven load spread.

 

It is always a good idea to know how close to the weight limit you are as roadside checks both at home and abroad are not unknown and it could be very inconvenient, and expensive, to be found to be overweight!

 

http://chrishodgetrucks.co.uk/useful-info/weighbridges.htm

[Woodlander]

Why is everything so complicated and technical with m/homes?

Thanks for the link. Will take your advice.

By the way - while it was difficult to fit two duvelays in the overcab storage of the Sundance, there is plenty of room for the foam toppers and sleeping bags. They handle much easier.

[flicka]

Once you have been over the weighbridge, this GUIDE is useful.

 

This pdf from tyresafe.org is a very useful guide to 'reading' a tyre - click to open in a new window.

 

 

It's a .pdf (Adobe) file, but I couldn't find the link on their current website.

Edit:- Link not working , sorry. Will try another way.

 

Try this link

http://www.motorcaravanning.com/vehicles/tyres.htm

 

& go almost to the bottonmof page for red text

"This pdf from tyresafe.org is a very useful guide to 'reading' a tyre - click to open in a new window."

[Woodlander]

Thanks Flicka - very useful

[Derek Uzzell]

I believe the Swift Sundance 580PR model was first marketed in the UK for the 2007 model-year and, therefore, will always be based on the current Fiat Ducato X250 chassis. Some brief specification details and photos of an example are on the following links:

 

http://www.swiftgroup.co.uk/uploads/HandBooks/motorhomes/2007%20MH%20Tech%20Books/Swift%20Sundance%20Tech%20handbook%202007.pdf

 

http://www.southernmotorhomes.co.uk/details.asp?ref=2875

 

The 580PR’s technical data indicate that the factory-fitted tyres would have been 215/70 R15 size and (normally) ‘camping-car’ type. Only Continental, Michelin or Pirelli have offered this type of specialized tyre, and it’s likely that Woodlander’s vehicle will have been fitted with (probably) Michelin “Agilis Camping” or (possibly) Continental “VancoCamper”.

 

‘Camping-car’ tyres are manufactured to be able to be run at high inflation pressures. The original camping-car tyre, introduced in the 1990s, was Michelin’s “XC Camping”.

 

When XC Camping tyres were fitted to Fiat-based motorhomes as part of Fiat’s Camping-Car Package (that, besides the specialised tyres, included suspension revisions) the Fiat Ducato handbook recommended inflation pressures for the 215/70 R15 tyre-size of 5.0bar (front tyres) and 5.5bar (rear tyres). The pressures recommended by the Fiat handbook for Ducatos with similar size (but non-camping-car type) tyres were 4.0bar/59psi (front tyres) and 4.5bar/65psi (rear tyres). While camping-car tyres may (when appropriate) be run at lower pressures, non-camping-car tyres should not be inflated to ultra-high pressures.

 

Inflating the tyres of a relatively small, light motorhome like a Sundance 580PR to 5.0bar(F)/5.5bar® will inevitably produce a firm ride on anything other than a billiard-table-smooth road surface. It should normally be permissible to reduce that firmness safely by downwards-adjusting those pressures, but (as has already been advised) it’s unwise to do this just based on guesswork – weighing the motorhome in fully-loaded state is essential to gain accurate axle-loadings, and subsequently seeking advice from the tyre manufacturer based on those loading figures is desirable.

 

5.0bar(F)/5.5bar® pressures have become the ‘standard’ inflation-pressure recommendation for 215/70 R15 camping-car tyres. Unfortunately, nowadays, rather than provide a pressure recommendation that directly relates to a quoted rear-axle loading, Michelin will usually just advise 5.5bar pressure for “Agilis Camping” tyres fitted to a motorhome’s rear axle.

 

Some bedtime reading…

 

http://www.outandaboutlive.co.uk/forums/search/query.asp?action=search&searchforumid=all&keywords=215%2F70&author=derek+uzzell&days=&Submit=Search

 

[Woodlander]

Thanks for that very comprehensive reply and the helpful links.

My tyres are Conti VancoCamper.

So it looks as though it's a visit to the weighbridge!

Hey-Ho.....

[Derek Uzzell]

Woodlander - 2012-07-29 8:56 AM

Thanks for that very comprehensive reply and the helpful links.

My tyres are Conti VancoCamper.

So it looks as though it's a visit to the weighbridge!

Hey-Ho.....

My experience of Continental is that, if accurate information is given regarding tyre details (in your case I'm assuming this will be "Continental VancoCamper 215/70 R15CP 109R"), together with front and rear axle-loadings (NOT the motorhome's overall weight) measured via a weighbridge, realistic advice on appropriate tyre inflation-pressures will be provided.Continental's contact webpage is here:http://www.conti-online.com/generator/www/uk/en/continental/automobile/functions/contact/contact_properties_en.html

[suntrecker38]

Hello Everyone

 

Thank you for the interesting read on the subject, but I have a problem. The other day I called at my local Leeds City council weighbridge to enquire about have the M/H weighed both axles and the gross, the weigh bridge operator told me that they did not weigh axle separately, council policy. Are they being awkward or is this a general thing. Or should I try and find another weigh bridge.

 

 

 

[Brian Kirby]

Not general, so try elsewhere. They are generally used for weighing bulk goods in, or out. So, most are set up for taking two weights, when a vehicle arrives, and again when it leaves. If set up for goods ion, therefore, all you have to do is drive on so that all 4 wheels are as central as possible and take weight 1 (which will be your actual laden weight), then drive forward until the front axle is just off the platform and take weight 2 (which will be your rear axle load), and the machine will calculate weight 3 (1 - 2) that will be the front axle load. If set up for goods out, you drive on as far as possible leaving the rear wheels just off the platform and take weight 1 (front axle), then drive fully onto the platform for weight 2 (actual laden), and the machine will calculate weight 3 (in this case2 - 1) that will be the rear axle load. If you tell the operator what you want they should understand. The machine will print the ticket with all three weights, you merely need to note which is which for future reference. Just make sure that it is fully laden, and that everyone, including the pet hamster, is aboard all the time.

[Tracker]

That should work Brian but the last time I used a weighbridge we weighed the two axles individually plus the GVW of both axles and the weight of the whole was about 50kg more than the sum of the two parts?

 

I don't know why and neither did the weighbridge operator but he did say that it was not unusual?

 

Physics theory was never my strong point but maybe something to do with leverage if the unweighed wheels are too far from the edge of the platform?

 

Individual axle weights are essential to calculate tyre pressures - more so than the GVW.

[silverback]

geeeeees tracker!! is this the grumpy git whats been on ere years? or someone else? i think you've reinvented yourself :D wheres the plug?

jon

[Brian Kirby]

Tracker - 2012-07-31 1:13 PM

 

That should work Brian but the last time I used a weighbridge we weighed the two axles individually plus the GVW of both axles and the weight of the whole was about 50kg more than the sum of the two parts?

 

I don't know why and neither did the weighbridge operator but he did say that it was not unusual?

 

Physics theory was never my strong point but maybe something to do with leverage if the unweighed wheels are too far from the edge of the platform?

 

Individual axle weights are essential to calculate tyre pressures - more so than the GVW.

I'll guess, but it is no more. Two possibilities.

 

First, accuracy at low loads. If it was a mechanical weighbridge, it may be that the read out is not accurate within 50kg. If electronic, it may be that it is not accurate at low loads, bearing in mind a lot of the vehicles weighed would be at least 7.5 tonnes, most more. Axles at 2.2 tonnes or under, is not really what they are good at.

 

Second, it may be that the approaches were not completely level, meaning there would be a small shift in the centre of gravity relative to the wheelbase as the van tilted first one way, was then horizontal,and then tilted the other way. At least the way I described will usually get you a printed ticket as evidence, should that be needed, and it does eliminate the problem you had.

 

It is probably unwise to try go get too accurate in any case, as the loads shift around as you buy and consume stuff along the road. I'd inflate for the higher load if in doubt, safer to be a bit high than to be low, after all.

[JohnP]

I have a Swift Bolero.

Plates at

3500kg Max Weight

6000kg Train Weight

1850kg Front Axel

2000kg RearAxel.

 

It is fitted with Continental VancoCamper 215/70 R15CP 109R

 

You must as others have said get your van weighed before adjusting pressures.

 

I weighed my van before my holiday and it came in as:

TotalWeight 3260kg

Rear Axel 1680kg

Front Axel 1580kg

 

Working from the information provided by Continental Tyres the pressures were reduced to

 

51 psi at front

64 psi at rear

which is considerably lower than Fiat or Swift quote.

Handling and ride have improved considerably at these pressures

 

Continentals number is 01788 566240

 

Hope this helps

[Woodlander]

Thanks muchly for that.

I like the sound of those pressures.

Like you, I don't think I will be anywhere near the GVW.

 

[lennyhb]

The pressures John suggests sound nearer the mark the ones swift recommend are likely to be for Michelin's they tend to run at higher pressures. For example my Hymer manual gives Michelin at Front 4.25 bar Rear 5.5 bar, all other makes Front 4.25 bar Rear 4.5 bar.

[rupert123]

You have to get it weighed and I am with Derek on this, Conti are very helpfull. The last time I had Conti tyres I telephoned them with the weights and they gave me the pressures over the phone and followed up with an email for my own records.

[Robinhood]

rupert123 - 2012-08-02 9:35 PM

 

Conti are very helpfull.

 

....indeed they are. And unlike Michelin (who I've found helpful in the past by email), they still make their technical data freely available for download, so you can make your own judgement about tyre pressures (as long as you've gone through the weighbridge process of getting real axle weights).

 

As posted on here previously - available at http://tinyurl.com/7crtn2e

[onecal]

Hi,

I think 55psi Front, and 65psi in the back, should be Ok,,,

Regards,

Brendan

[Derek Uzzell]

lennyhb - 2012-08-02 5:32 PM

 

The pressures John suggests sound nearer the mark the ones swift recommend are likely to be for Michelin's they tend to run at higher pressures. For example my Hymer manual gives Michelin at Front 4.25 bar Rear 5.5 bar, all other makes Front 4.25 bar Rear 4.5 bar.

 

That's too simplistic nowadays, I'm afraid.

 

When Michelin was the only company marketing 'camping-car' tyres, motorhome manufacturers were able to recommend one set of inflation pressures for the Michelin "XC Camping" pattern (when the vehicle had been fitted with those tyres) and another set of pressures when the vehicle was fitted with tyres from any other manufacturer. For example, for a Hobby motorhome fitted with 215/70 R15C XC Camping tyres, the 2004 Hobby manual recommended 4.5bar(F)/5.5bar®. For a Hobby motorhome fitted with any other 215/70 R15C tyre, the Hobby manual recommended 4.0bar(F)/4.5bar®.

 

This type of recommendation is no longer practicable, as more than one tyre manufacturer now markets camping-car tyres. The best a motorhome manufacturer can do is recommend one set of inflation pressures when the vehicle is fitted with camping-car tyres and another when it is not.

 

As all tyres with a similar specification will have similar pressure-to-load figures, as far as suitable tyre-pressures are concerned it's largely irrelevant whether a motorhome is fitted with 215/70 R15C Continental VancoCamper, 215/70 R15C Michelin Agilis Camping or 215/70 R15C Pirelli Chrono Camper tyres. These are all camping-car tyres and, for a specified axle-load, will require much the same inflation pressure to support that axle-load safely.

 

So, if suitable inflation pressures (based on weighbridge-measured axle-loadings) have been established for a motorhome fitted with 215/70 R15C Continental VancoCamper tyres and one or more of those tyres subsequently needs to be replaced with, say, 215/70 R15C Pirelli Chrono Camper tyres, there should be no need to alter the established inflation pressures. Conversely, if the 215/70 R15C Continental VancoCamper tyres are to be replaced by a significantly different specification tyre (eg. a non-camping-car tyre), it's likely that the pressures will need to be adjusted accordingly.

 

Length = 6.32m Height = 2.96m (Swift Sundance 580PR)

Length = 7.04m Height = 2.77m (Swift Bolero 680FB)

 

It should be apparent from the above data that, even if both motorhome models share an identical tyre specification, the dimensional variations are likely to produce different axle-loadings when each vehicle is loaded up by its owner. That's why it's important to weigh the vehicle to measure the actual axle loadings.

 

It may be that the 1580kg(F) and 1680® measured axle-loadings of JohnP's Bolero do match the axle-loadings of Woodlander's Sundance when it's weighed, in which case 51psi(F)/64psi® should be suitable inflation presuures for the latter vehicle's tyres. But, unless the Sundance is weighed its axle-loadings will continue to be an unknown quantity, as will the most suitable inflation pressures.

 

Playing about with tyre pressures on a 'by Guess and by God' basis is hardly the most scientific approach and I'd be interested to learn what criteria Brendan has used to arriive at his 55psi(F)/65psi® "should be OK" advice.

[Brian Kirby]

I strongly agree with Derek. Guessing is as likely to result in under inflation for the load (which is dangerous because it causes the tyres to over heat, possibly leading to an explosive failure), as over inflation (which can upset the handling and ride a bit, but at least won't kill you).

 

If you wish to depart from manufacturer's recommended pressures it is essential to take the fully laden van, (meaning complete with full water tank, full fuel tank, all gas cylinders full, all passengers, and pets etc, all food drink, clothing, camping gear, bikes, scooters: the absolute lot!) and get the weights on each axle, plus the van, with everyone (including the driver!) remaining on board.

 

To be sensible, you need to add a margin to those individual axle loads to account for the way load transfers around the vehicle as you consume and replenish food, drink, water and fuel, especially if your van has a long rear overhang with storage space behind the rear axle. Also consider the position of the grey water tank, and with rear washroom models even the toilet cassette, remembering that 1 litre of water weight 1 kilogramme.

 

If not prepared to do the above, the only safe advice is to stick to the manufacturer's pressures. These pressures are for the maximum permissible load on each axle (which, should you ever achieve that state, would result you exceeding the MAM for your van). Since the manufacturer cannot know what loads you will put where, they are the only safe recommendation that can be given. The inevitable result is that at least one, and possibly both axles, will be over inflated for actual loads, which does result in a hard, and sometimes twitchy, ride, but at least the tyres will not overheat and be prone to blowing out!

[onecal]

Hi,

Think boys you really have lost the plot,,,,,,keep an eye on said rubber and feel them now and again, for overheating. On the said OP vehicle ,,,unless overloading, 55 front and 65psi rear should be adequate.

Yes I agree  overloaded and under inflated tyres will overheat and blow ,,,,,as will over inflated ones that are not fitted with steel valves,,,,,So go to weighbridge , check the vans weight , contact a good tyre manufacture (like the ones fitted one your Motorhome) re:- tyre pressures and find what pressures suit your van/Motorhome/tyres. Also check them often for damage and pressure when cold and overheating after a short run,

Regards,

Brendan