Tag axle Vs twin wheel

Discussion in 'Motorhome Chat' started by jacken, Dec 27, 2007.

  1. jacken

    jacken Read Only Funster

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    Hi,

    As I was reading the latest MMM and the review of the tag axle motorhome, it set me wondering. What are the merits or otherwise of using a tag axle, over the twin wheel axle of say, a 'Trannie' or Merc?. I always thought that tag axles scrub out tyres more due to the way they slide around corners. Also, what about payload of each. Which can carry the most? I assume cost comes into it as well. Is it cheaper for a convertor to buy in a tag axle 'Bogey' than use a twin wheel Transit or Merc?.

    Just my enquiring thoughts.

    ken
     
  2. pappajohn

    pappajohn Funster Life Member

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    hi ken,
    i really dont know the answer to this one but my views are:-

    if twin wheels were the answer then why dont the manufacturers use them.
    probably because of the suspension geometry on alko type chassis, which seems the popular choice, on large motorhomes. cant see how twin wheels can be fitted to a trailing arm torsion bar setup as it would be too far outboard of the chassis and need to be soooooo heavy to cope with the bending effect.

    twin axles should carry more weight than a single axle ie- larger, rigid hgv's.
    hence heavier, larger body and more payload.
    i'v only ever seen twin wheels on a standard rear banjo axle


    it will probably allow a longer overhang which, by law, has a maximum of 60% of the wheelbase behind the rear wheels. hence longer body.


    saying all this any manufacturer using standard tranny/merc chassis would probably go for a twin wheeler for the extra weight/payload over a singe wheel axle.


    apart from all this they do look the dogs do-da's. :thumb:

    just my opinions,

    john.
     
  3. Jim

    Jim Ringleader

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    I was told that a twin wheel will have a greater towing capacity than a tag. If this is true, I have no idea why,
     
  4. pappajohn

    pappajohn Funster Life Member

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    maybe the extra weight the twin wheel, over a single axle,single wheel, can carry, jim.
    its a bit like the caravan tuggers, big van needs a big car and not just for more power.
    anything approaching 2 tonne will need a big 4x4 for the weight even though a 2 / 2.5ltr car has the ability

    john.
     
    Last edited: Dec 27, 2007
  5. johnsandywhite

    johnsandywhite Read Only Funster

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    :Cool: The advantage of a Tag axle as against twin wheels is that it allows a longer wheel base and perhaps some extra load capacity. Our Newmar has both. :Wink:
     
  6. jacken

    jacken Read Only Funster

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    Would this not be because twin wheels are normally rear wheel drive. Which begs another question. Are pushers better for towing than front wheel drive? Now my 6 tonne chassis, according to the book, has a payload of 1200kg and will tow 2000 kg, apparently.

    ken
     
  7. pappajohn

    pappajohn Funster Life Member

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    my kontiki, at 3.85ton, has a towing limit of 2 tons. i believe all fiat/peugeot vans have this limit.
     
  8. Tony Santara

    Tony Santara Funster

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    Towing limits aside, double wheels will give you better grip on softer ground, because you will get more tyre on the ground than with a tag axle which takes weight off your drive axle also when turning on soft ground their will be less drag
     
  9. Supertractorman

    Supertractorman Read Only Funster

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    My Bessie at 4 tons only has 1500 kgs towing capacity

    David
     
  10. cabby

    cabby Deleted User

    the reason that most motorhomes are alko chassis or even tag axle is simply cost. a FWD is cheaper than a RWD.if it was the other way round then you would see more trannies or mercs than Fiat/Pug.plus bulk purchase as well.
    Having had both I prefer the RWD which gives a smoother ride.

    cabby
     
  11. pappajohn

    pappajohn Funster Life Member

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    I stand corrected..........:Blush:
    may be something to do with the model/year.
    mine is a 2001 pre jtd and the handbook says all ducato's are rated at 2 ton.

    john.
     
  12. Supertractorman

    Supertractorman Read Only Funster

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    John,

    I did read somewhere that 2.8 Ducato chassis were originally based at 3.5 ton and 2 ton towing but if increased in any amount up to 4ton, then towing capacity compensated, but yours contradicts this. I wonder if the Alko chassis (or not ) has anything to do with this?.

    David
     
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