Auto-Sleeper Sussex Duo tyre pressure

Hi all, we recently purchased an Auto-Sleeper Marquis Sussex Duo - can anyone advise me on the tyre pressures for this vehicle .

The only pressures that AS, or indeed Peugeot will quote and stand by, are the ones shown on the sticker in the passenger door shut. From memory they are 60 psi front and 65 psi rear.

Out of interest I asked a couple of salesman's at the NEC show last week what the tyre pressure should be for our 2011 Symbol. There response was that they were not allowed to tell me or recommend a tyre pressure!
Its a bit strange, yes we have the stickers on the vehicle, but its not a van any more..

mike

daveH wrote:Hi all, we recently purchased an Auto-Sleeper Marquis Sussex Duo - can anyone advise me on the tyre pressures for this vehicle .

We have 119 threads on this subject.It comes up for all models.
There is a factsheet that will help you decide when you have weighed your vehicle.
As all motorhomes are different weights,there is not one tyre pressure to quote.

regards

Micky

mpbarrett wrote:Out of interest I asked a couple of salesman's at the NEC show last week what the tyre pressure should be for our 2011 Symbol. There response was that they were not allowed to tell me or recommend a tyre pressure!
Its a bit strange, yes we have the stickers on the vehicle, but its not a van any more..

mike

It is a vehicle with a MGW of 3500kg and that is what the sticker in the door shut is for. It matters not at all what its present use is for, or how it has been converted into whatever it is, the only factor that either Peugeot or AS will acknowledge is its MGW.

There are threads from other forum members which quote lower pressures based on tyre manufacturers recommendations for various load / speed / temperature conditions, perhaps a search of these might help?

This statement is from a passed issue of the CC magazine.
'The label beside the door is most likely applied by the base vehicle manufacturer on the production line and relates to the state of the vehicle at that time. When the motorhome conversion is done, the maximum weight of the vehicle may increase, and/or the wheel and tyre  specification may change. The advice in the handbook should reflect those changes and therefore should be correct for the finished motorhome. Where changes during conversion affect the tyre pressures required, the converter should really remove the superseded advice by the door.

Spospe wrote:

mpbarrett wrote:Out of interest I asked a couple of salesman's at the NEC show last week what the tyre pressure should be for our 2011 Symbol. There response was that they were not allowed to tell me or recommend a tyre pressure!
Its a bit strange, yes we have the stickers on the vehicle, but its not a van any more..

mike

It is a vehicle with a MGW of 3500kg and that is what the sticker in the door shut is for. It matters not at all what its present use is for, or how it has been converted into whatever it is, the only factor that either Peugeot or AS will acknowledge is its MGW.

There are threads from other forum members which quote lower pressures based on tyre manufacturers recommendations for various load / speed / temperature conditions, perhaps a search of these might help?

Weighing is always the best thing to do, but as long as you did not do that , you must go from the MPAW and MPVW.
that is what the original carmaker also uses for their advice.
But for a Motorhome its a bit differentf, especially those for B-driverslicence ( live in Holland , mayby different for you ), with max allowed weight of 3500kg. 
These motorhomes are ,1: mosty overloaded on MPVW, and MPAW Rear.
Between tire-makers and Motorhome makers this is a Public secret, and also most users know this.
This means that you cant go from the car-makers advice for rear.
Rear must be mostly maximum of tyre and this is in Europe with mostly 8PR tyres , 65/70psi/4.5/4.8 bar, will call it AT-pressure furtheron, because its mostly written "maximum load single xxxx kg AT yyy psi ( cold)".
The tyre maker does not allow more anymore, in earlyer days they did up to 10 psi/0.7 bar.
Now there is a Special Camper tyre from Michelin ( XP)  and Continental ( Vancocamper), for wich tyremaker allows higher then the 8PR values , and is maximum allowed cold pressure of 5.5 bar/80 psi, while the AT-pressure is still that 69/70psi/4.75/4.8bar( cold).

Here the tyremaker does not support higher then maximum load above that AT-pressure, but in fact they  advice 80 psi to cover that higher load because of overloading, a double moral .

But for front axle you can go with lower pressure , because front axle is almost impossibly overloaded.
I even determined a motorhome standard , and that is next.
Expected weight on front axle for motorhome fully loaded is MPVW- MPAW-rear.
Example MPVW= 3500 kg , MPAW-rear= 2000 kg, then expected weight on front axle= 3500kg-2000kg=1500 kg, while MPAW-front is probably about 1750 to 1900 kg.

So after this long explanation , my advice will be , as long as you did not weigh,  Front about 3,5 bar/51 psi, and rear 5.5bar/80 psi ( if allowed because of special camper tyre.
Even if yust normal 8PR C-tyre, this 80 psi rear would be advicable , but tyremakers dont allow it anymore.
But you can always say you filled that 65/70 psi written on sidewall, at zero degrees C/32degrF, and it has risen by temperature rising to 18 degr C/65 degr F  to that 5.5bar/80psi.
Once read that tyres are tested to can stand  2 to 3 times the AT-pressure. Also the valves can stand higher pressure .

So try to give me as much possible and acurate data and I will calculate a save pressure-range for you .
Greatings from a Dutch Pigheaded Selfdeclared Tyrepressure-specialist"
Peter

Spospe wrote:

mpbarrett wrote:Out of interest I asked a couple of salesman's at the NEC show last week what the tyre pressure should be for our 2011 Symbol. There response was that they were not allowed to tell me or recommend a tyre pressure!
Its a bit strange, yes we have the stickers on the vehicle, but its not a van any more..

mike

It is a vehicle with a MGW of 3500kg and that is what the sticker in the door shut is for. It matters not at all what its present use is for, or how it has been converted into whatever it is, the only factor that either Peugeot or AS will acknowledge is its MGW.

There are threads from other forum members which quote lower pressures based on tyre manufacturers recommendations for various load / speed / temperature conditions, perhaps a search of these might help?

Actually I have searched and read the other posts. I really posted my comment out of interest as I thought Autosleeper would have been more helpful and I was a bit surprised by there response. They could have just said see the sticker and use those pressure. That's all.
mike

In my former reaction here, I tried to explaine why , for motorhomes up to 3500kg , the pressure should be different from car-makers advice , but also different from Motorhome-makers advice.
For tyrepressure advice best is to follow the rules of nature, so your tyres wont be overheated at any spot.
And the built of a motorhome, makes that rear axle gets more weight on it , then the car-makers uses for its advice.

But the motorhome maker nowadays , give , if the special camper tyres , all around an advice of 5.5bar/80psi, wich is for rear yust needed to cover the overload and unequall load R/L, but for front exagerated because front can impossibly be overloaded by the way you can load a motorhome. This gives discomfort because driver and co-driver are seated closer to the front axle, and gripp is less , wich is needed for braking( front more then rear) and to get a way on slippery underground for the mosty frontwheel drive motorhomes.
For mother nature only the real weights on tyres count and the speed you drive.

some additional info:
Cold pressure is when inside tyre temp = outside tyre( ambiënt) temp, that simple.
so this is not when driven for a while.

Warm pressure is higher because inside tire temp rises, when ambiënt temp is 18 degrC./65degrF , and driving about 90km/55m/h, to about 40/45degrC/ 110/120 degr F., to about 10/11% higher pressure.

If you would fill a tyre at 1.4 times the AT-pressure ( that 70psi/4.8bar) at zero degr C/32 degr F , and by severe braking when descending the mountains, temp in tyre rises to boiling point of water ( at 1013mb, so 100 degr C/212degr F) , the pressure inside rises to about 2 times the AT-pressure.
Tyres and valves are made so they can stand it.
A valve importar once wrote me that this 100 degr C , can incidentially be reached in tire ( by that descending from mountains and braking to often). For Valves he gave me the standards for it, and given maximum of valves is cold at about 18 degr C/65degr F.
In races inside tyre often reaches 90 degr C/??F.

Goal of pressure advice determination is to keep every part of the rubber of tyre , below a sertain temp , at wich to much sulfur bridges ar made, by wich the rubber hardens at those rings, and damage at next bendings of it, by the deflections of the tyre.

Realise that when driving about 50m/80km/h, every segment of the tyre, deflecs and flexes back , about 10 times a second, wich produces heat .
More speed means more cycles a second and so more heatproduction.
Cooling down of tyre is depending on temperature differences between rubber and surounding rubber,  rubber and in- and outside-tire temp, and temp difference between in- and outside tyre temp.

First thought it was also dependent on speed, but on the ground the tyre has zero speed, and at the top of tyre , the speed is more then 2 times the speed of car, but in the wheelcase so no airstream around it.

A man of a tyre-maker once told me this in a long telephone conversation , so this is the real goal for tyrepressure-determination for tyre- and car-makers.

That the salesmen of the NEC did not want to give advice , has everything to do with the public secret about the overloading and unequal loading of the tyres for motorhomes, wich is not allowed by law.
If their advice would be to low ( even if that 80 psi) , because of the 1% exessive overloaded motorhomes, they could be held responcible for the accident it cources, with damage and mayby even injuries.

That is also my disclaimer: If my determined  advice-pressure is to low, ( because real loads and speed are higher then what I used for the advice) , I dont accept responcibility for it.
This makes clear the importance of determining the loads on tyre and maximum speed you wont go over for even a minute as acurate as possible.
But also mind misreading of pressure , no device is 100% acurate, and worst case schenario is that it gives 5% to 10% to high pressure.

If i may say so this is a long windy advisory.
I have a 3,500 and my rear tyres pressures are 65PSI.
If you weigh your motorhome and use the tyre pressure chart we have here you will be 100% safe.This has been good advice for many years.
Tyre pressures are a compromise for many factors.So a few pound either way is not the end of the world.

Micky

59 65
PeteJ