tyre pressure

[fireman1201]

Hi everyone does 5.5bar (79psi) sound ok for a fully loaded autotrail apache 700 (2008 heavy model with 16" wheels) as any info found is as clear as mud (?)

[Brambles]

Hi.

First of all check what the max pressure rating is on the tyres themselves. It should be moulded into the side wall. If they are michelin camping then 80psi is the max. Some continental camping are 69psi max.

 

In the meantime until you find out what the pressures should be, then 79psi in raer is probably fine (assummining tyre spec allows this pressure), but the fronts should be a lot lower and I would suggest 65psi max. If a pressure more than this is required then your front suspension is well overloaded.

 

How to find pressures? Unfortunately no short cut to this. With vehicle fully loaded and in running order you need to find a weighbridge and get the axles weighed. Contact the tyre manufacturer and ask for recommended pressures for those axles weights.

Jon.

 

[fireman1201]

the tyres fitted are conti vanco camper tyres and say 69psi max but the fiat handbook says 5.5bar (79psi) front and rear when running this size tyre and van

[rupert123]

fireman1201 - 2011-06-05 3:03 PM

 

the tyres fitted are conti vanco camper tyres and say 69psi max but the fiat handbook says 5.5bar (79psi) front and rear when running this size tyre and van

 

I to have Conti Vancos tyres and the company are very helpfull. As Jon (Brambles) has stated the only way is to get the van weighed and telephone or email Conti for pressures.

[Robinhood]

The only fully safe way to get an answer is to do what Jon and Rupert have suggested.

 

If you want a quick result, however, I'd suggest that you could immediately check your max front and rear axle weights, (above which use would be illegal anyway) and use the (customer services) contact facility here:

 

http://www.conti-online.com/generator/www/uk/en/continental/automobile/functions/contact/contact_properties_en.html

 

.........detailing those weights, and the specific tyres and size that you have, and ask for recommended pressures for those loadings.

 

I believe you F/R max axle weights are 2100kg/2400kg respectively, and the tyres are probably 225/75 R16CP Vanco Campers.

 

If you quote these, I wouldn't be suprised if they recommend something in the region of 57F 69R but I am not an expert, and they are certainly not a recommendation from me. I am simply extrapolating from a set of Continental technical data I have downloaded, and which surprisingly agrees with the door pillar pressures on my van (which is a first).

 

If they do recommend pressures (well) below the 5.5 bar, then handling and ride are likely to improve.

 

If you take the quick route, I would still advise the weighbridge check, but you will already have a set of tyre pressures relevant for the maximum weights at which your 'van should operate. Patently, if one or other of the actual axle weights is lower than those above (which should be the case if you are legal) you could put in another request with those weights.

[Brambles]

fireman1201 - 2011-06-05 3:03 PM

 

the tyres fitted are conti vanco camper tyres and say 69psi max but the fiat handbook says 5.5bar (79psi) front and rear when running this size tyre and van

 

When vehicle manufactures build a chassis they have no idea what conversion is going onto the base vehicle and final weights. So they specify the max tyre pressures for the tyres they fit.

They have a requirement to fit a label in the door piller showing the max tyre ratings for tyres fitted when built. This is the maximum pressures permissable for the tyres fitted. They may sometimes include a correction factor or chart for lower loadings. If the convertor or owner changes the tyres at a later date then the labels are no longer applicable.