Tyre pressure advice please

Discussion in 'Motorhome Chat' started by Nirvanauk, Apr 16, 2013.

  1. Nirvanauk

    Nirvanauk Funster

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    I have a PVC based on a Renault Master van. The Renault book advises 3.8 bar in the front and 4.4 bar in the rear. This is what I have always used, however got to thinking that I need to up this as it has the extra weight of a conversion plus tow bar etc.
    Any advice please?
    Many thanks
     
  2. canopus

    canopus Funster Life Member

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    Contact the tyre manufacturer :thumb:
     
  3. mikebeaches

    mikebeaches Funster

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    Ah, the black art of determining motorhome tyre pressures. :Eek!:

    Load up, go to a weighbridge to check how much weight is on each axle and the total for the van then, as already mentioned, send a question about the correct pressure to the tyre manufacturer.

    However, if it's got Michelins fitted (turn on cynical mode) don't expect anything other than a recommendation of 80psi on the rear.

    If you've got Continental, then you should get a really helpful reply. Can't speak for other manufacturers.

    Mike

    PS My experience of Michelin is that if the word 'motorhome' is uttered, they automatically advise 80psi on the rear.
     
  4. normanandsue

    normanandsue Funster

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    I can confirm this but are you suggesting this is incorrect?

    Norman
     
  5. mikebeaches

    mikebeaches Funster

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    Well yes, in many/most cases I think it is.

    Michelin have stated on a number of occasions that because - in their words - 'motorhomes are usually overloaded', we recommend the rear tyres should run at the maximum recommended pressures ie 80psi.

    The problem from my personal perspective is that our rear axle weight is never anywhere near the designed max loading, and the same goes for the overall weight of the van. The fact is 80psi on the back gives a bone-shakingly, and possibly dangerous (in my opinion) ride.

    When we picked up our van new and therefore pretty much empty, the supplying dealer, as part of the pdi, had inflated all the tyres to 80psi. We had a one-hour journey on the motorway to get home. It was dreadful, and the van was wandering all over the place - completely unstable. Not to mention, harsh in the extreme.

    I suspected the tyre pressures straight away. Fortunately, the new van was fitted with Continental tyres and, as indicated in my previous post, after I'd supplied the relevant weights, they're recommended pressures were much lower. The driving was transformed - a great deal more comfortable and always now feels completely stable on the road.

    I had Michelin tyres on a previous van, and hence my experience with them. And I've seen lots and lots of posts where others have mentioned the same thing about the rear pressures they advise. :Sad:

    Mike
     
  6. pappajohn

    pappajohn Funster Life Member

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    never exceed the max pressure stated on the tyres.

    are your tyres wearing on the outside edges more than the centre ?
    do your tyres run hot and feel sticky, more than hand warm, on long runs ?

    if no to both then your pressures are just about right

    over inflation causes excessive wear in the centre of the tread.
    under inflation causes excessive wear on the outer edges
     
    Last edited: Apr 16, 2013
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  7. Microchip

    Microchip Funster

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    We went to Hymer in Bad Waldsee Germay for parts last year, and just for interest sake I asked what pressure my tyres should be.

    Being a 3.5 ton van they said 4 bar front and 4.5 bar rear, when I checked I had 4.5 front and 5.5 bar rear, so I let a lot of air out and we had less rattles and a more comfortable drive home. :thumb:

    Keith
     
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