Tyre Pressures

What drove me nuts is the difference in opinions and advice. I took some convincing that you can lower the pressures on CP tyres. Both my local garage and the large garage chain that does my servicing recommended the maximum 80 PSI so you would expect them to know right? Well it turned out the large garage get their advice from one of the big caravan and motorhome dealers so you would think they would know right? Well I then consulted on advice on here with Conti tech department and thats where they confirmed you can run them much lower depending on your "actual" weight you are running at on both axles which was what a lot of people said on here.
 
Im 65psi all round but must say i have double wheels at the back and she drives nice, i did try 80psi and it was like driving on solid rubber, van is 4.3 ton but light running weight.
 
Another tyre pressure thread!!!!!! :LOL:

thriller-michael.gif
Not had a gassing thread for ages
 
New Rimor on a Fiat Ducato base.

Plate says 79 psi, tyres say 69 psi.

Hmmmm?
Nobody can tell you the correct tyre pressures for your van. You need to load it FULLY with everything, food, fuel, water, passengers and all. Then take it to a weighbridge to get the individual axle weights. Write then down - you could misremember.
Once you know the axle weights, read the load rating and maximum pressure written on the tyres.
The load rating is the maximum load for that tyre (so double it for the axle) at the maximum pressure writrennon the tyre.
The correct pressure is proportional to load.
For example, if the load rating is 1400kg at 65psi max pressure, and your measured axle weight is 2200kg, the correct pressure is (2200/2) / 1400 x 65 = 51psi.
Under inflation is worse than over inflation, so I suggest adding another 3psi, giving a result in this made-up example of 54psi
 
Nobody can tell you the correct tyre pressures for your van. You need to load it FULLY with everything, food, fuel, water, passengers and all. Then take it to a weighbridge to get the individual axle weights. Write then down - you could misremember.
Once you know the axle weights, read the load rating and maximum pressure written on the tyres.
The load rating is the maximum load for that tyre (so double it for the axle) at the maximum pressure writrennon the tyre.
The correct pressure is proportional to load.
For example, if the load rating is 1400kg at 65psi max pressure, and your measured axle weight is 2200kg, the correct pressure is (2200/2) / 1400 x 65 = 51psi.
Under inflation is worse than over inflation, so I suggest adding another 3psi, giving a result in this made-up example of 54psi
Exactly this, its the only way to do it properly ....!
Nice to see intelligent advice, rather than heresay or misinformation....
 
I tend to disagree the tyre pressures are set by the manufacturer and that is what I use for my car n van . , my van,can carry 200 litres of water and a 100 litres of fuel the debate goes on and on .
 
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TyreSafe will generally give good advice BUT they quote figures based on the MAXIMUM axle load ("because it might be").
When "researching" for my previous 2.7l Merc Sprinter-based Rapido, one major tyre company website took my registration and told me it was a 2.2l Merc car and required pressures of 35psi all round! Look very carefully at what you are told!
 
I tend to disagree the tyre pressures are set by the manufacturer and that is what I use for my car n van . , my van,can carry 200 litres of water and a 100 litres of fuel the debate goes on and on .
The van manufacturer gives the tyre pressures based on maximum axle loads, if you are running at those maximum axle loads, fine, but if you are running less than the maximum axle loads then the tyres are over inflated. As Barry posted, Conti will give you recommended tyre pressures based on the axle loads that you actually run at.
Take my van, the manufacturer gives tyre pressures based on 2.1t front axle, and 2.4t rear axle, so that's 4.5t in total, but the van is sold as only being 3.5t.
 
Bit worrying that the van has been supplied with tyres that have a maximum pressure of less than the recommended tyre pressure.
 
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