Hi. I checked the tyre pressures on my Ducato motorhome today. The plate on the body says they should be 79.5psi all round. The front 2 were 75psi. The back 4 on tag axle were around 55psi. I have inflated to 79psi. Is this correct or is there some reason the garage / previous owner had them at this pressure.
General Tyre pressures
- Thread starter bigbag
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General Tyre pressures
Caravadossi
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What tyres are you running on?
How does the vehicle tyre spec compare with the spec of the tyres fitted?
Maybe(?) the previous owner/dealer has kept the psi within spec of the respective tyres.
042130Z
How does the vehicle tyre spec compare with the spec of the tyres fitted?
Maybe(?) the previous owner/dealer has kept the psi within spec of the respective tyres.
042130Z
"The ETRTO also states that where CP tyres are used on the rear axle
(single fitment), they must be inflated to a pressure of 5.5 bar instead
of the normal pressure of 4.75 bar for example.
l MICHELIN CP marked tyres are therefore specially designed to be driven
at an inflation pressure of 5.5 bar (550 kPa) This higher pressure improves
road holding and increases resistance to the challenging driving and usage
conditions encountered by motorhomes, especially with regard to loads
(occasional static and/or dynamic overload associated with this type of vehicle;
considerable rear overhang, load imbalance, high centre of gravity due to
highly positioned loads) and long-term periods of disuse."
In general inflation is related to load and tyre size, with a tag axle and under max load I think 79psi will be horrible.
You can contact your tyre manufacturer for technical advise.
(single fitment), they must be inflated to a pressure of 5.5 bar instead
of the normal pressure of 4.75 bar for example.
l MICHELIN CP marked tyres are therefore specially designed to be driven
at an inflation pressure of 5.5 bar (550 kPa) This higher pressure improves
road holding and increases resistance to the challenging driving and usage
conditions encountered by motorhomes, especially with regard to loads
(occasional static and/or dynamic overload associated with this type of vehicle;
considerable rear overhang, load imbalance, high centre of gravity due to
highly positioned loads) and long-term periods of disuse."
In general inflation is related to load and tyre size, with a tag axle and under max load I think 79psi will be horrible.
You can contact your tyre manufacturer for technical advise.
Last edited:
boringfrog
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The plate on the body will be for a standard van not a motorhome.
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Thanks all for the advice. I'm still confused. When inflated to 79psi there seemed to be a marked improvement in handling. Do you think the dealer will know the correct pressure. Seems a big difference from front and rear when front were at 75psi and rear at 55 psi. Would this be because of the tag axle?
I agree the plate could be for a van as it shows a single rear axle.
I agree the plate could be for a van as it shows a single rear axle.
In that case you're running over 90% of max load all the time with just the wife, water, gas, diesel and a few small provisions on board so those pressures sound about right .. just make sure the tyres fitted can take that pressure. Also check the valves, tyre shops often put normal valves on which aren't rated for that pressure.
I have a swift kontiki 2004 with michelin campers 215/75/16 i keep tyre pressure at 80 all round had these tyres since new thats almost ten years still plenty of tread on them but the outrr side walls are starting to perish so i am looking to replace them question. Do i put same back on or go for cheaper truck tyres? Are motorhomers being conned. I am now using my MH all year round
Caravadossi
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What-tyres-are-you-running-on?
215/70R16 Load/Speed? Make/Model? Max Pressure? (all info is on-the-tyre!)
5 tonne sitting on 4 tyres = 1.25/tyre = Load: 116
Presumably then …
5 tonne sitting on 2x4 = 1.25/front tyre (Load 116) + 625kg/rear tyre (Load 92)
Assuming a 20% margin …
6 tonne sitting on 4 tyres = 1.5/tyre = Load: 122
6 tonne sitting on 2x4 = 1.25/front tyre (Load 122) + 750kg/rear tyre (Load 98)
I’m not sure if that’s the-way-it-works … but we’ll have a better idea when we know the info off the tyres on the vehicle
091043Z
The ones on mine when I bought it were normal van tyres, with a max psi of 60 on the sidewall.
They also had normal rubber push in valves, again only rated to 60psi.
If you need higher, you need to check the tyres are marked to whatever psi you run at, and ensure you have metal screw in valves.
They also had normal rubber push in valves, again only rated to 60psi.
If you need higher, you need to check the tyres are marked to whatever psi you run at, and ensure you have metal screw in valves.
maingate
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The first thing you need to do is get your van on a weighbridge. I also have a 5 tonne MAM Burstner Tag Axle and due to the layout, I can easily go well over the front axle weight limit of 2,000 Kg.
Your front axle tyre pressures sound about right, I run mine at around 75 psi, anything around 75 to 80 is OK. The rear axles could be a little lower than 55 but I would leave them as they are. mine are actually higher than yours. My reason for this is that motorhomes spend a lot of the time standing around and my opinion is that the tyre walls last longer with the extra pressure.
Your front axle tyre pressures sound about right, I run mine at around 75 psi, anything around 75 to 80 is OK. The rear axles could be a little lower than 55 but I would leave them as they are. mine are actually higher than yours. My reason for this is that motorhomes spend a lot of the time standing around and my opinion is that the tyre walls last longer with the extra pressure.
Caravadossi
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What tyres are you running on?
As an example – let’s say your front tyres are
ContiVanco2 215/75R16C 116R
giving a max load of 1275kg & max pressure of 75psi
092057Z
maingate
New member
Using Michelin Agilis 215/75R16 CP 113R
They are the recommended tyre and rating for the vehicle. The rating is pretty borderline that is why I put the van on a weighbridge. There is no spare capacity so I have removed the Super King Size mattress (we don't use the overcab bed), I travel with a minimum of fresh water and there is only 2 of us (plus the dogs).
Remember that the 2,000 Kg axle weight is carried by BOTH tyres, that is 1,000 Kg per tyre.
Caravadossi
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The 1275kg/75psi was based on an individual front tyre.
The error in my thinking was that the load sits squarely on the 4 (or 6) wheels.
I see now there’s more to it.
Michelin (as one might expect) provide detailed guidance. They advise the load on each individual tyre should be measured - & where there is load variation between 2 tyres on the same axle, then both tyres should be pressurised to the higher load value.
But help me out – what load/inflation table provides for the stated 75-80psi for a 113R tyre?
100932Z
Ten years and you're complaining about the price! With that low mileage and your van sitting around all the time you need the camper tyre. You'd be lucky to get 2-3 years out of a normal van tyresidewall standing around like that.
His head bowed,his feet shuffelling he was suitably chastised! Ahh
But if the EU has its way and forces people to replace their tyres every two years or so (which i read in the mail, so it must be true) surely it makes sense to go for the cheaper option and as i said i will be almost fulltime so not a lot of standing around.
But if the EU has its way and forces people to replace their tyres every two years or so (which i read in the mail, so it must be true) surely it makes sense to go for the cheaper option and as i said i will be almost fulltime so not a lot of standing around.
Caravadossi
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What is the max load/pressure given on the sidewall? (1150/65)?
It seems a bit of a tangled-web to me with no clear legal view of what is an `over-inflated tyre’
Michelin are obviously in the medal winners - what about the lower tier offerings? Barum? etc
101238Z
1150 single or 1090 dual is dual meaning for twin wheel?
