Importing a New Machine From The USA

[Philip Watkins]

One thing that tends to be mentioned with converted road trucks and wide tyres is that they regularly break half shafts due to the stress imposed on them by tyre resistance during turning.

When the Big A turns on wet grass you can hear a kind of whine as the inside of the tyre scrubs on the grass because it’s trying to cover much less distance than the outside of the tyre, or maybe vice versa.

On a truck, would this be reduced with dual wheels? Would each of the duals relieve it’s own stress within its own width, therefore not transferring it to the other tyre? Or would it be worse because the outer tyre could create more “leverage “?

Sorry, I’m not sure I’m using the right terms, I never was much good at physics.

..

I think I know what you're trying to say. I don't think it will matter whether it's duals or wide single wheels, it's overall width (and contact area) that is the problem. I wonder if the offset makes a difference, if you take it out to 3m might make things worse.

 

[Shovelhands]

Will need a wide track axle with nice big hub reductions for the job.............. similar to a Big A....

 

[Cab-over Pete]

You just can’t beat them !!

I’ve never thought of that. Does the wide track axle go some way to dissipate the stresses from the wide tyres?

 

[Zebbedee]

The least stress will be when the mounting dish is in the centre of the rim

 

[powerfarmer]

One thing that tends to be mentioned with converted road trucks and wide tyres is that they regularly break half shafts due to the stress imposed on them by tyre resistance during turning.

When the Big A turns on wet grass you can hear a kind of whine as the inside of the tyre scrubs on the grass because it’s trying to cover much less distance than the outside of the tyre, or maybe vice versa.

On a truck, would this be reduced with dual wheels? Would each of the duals relieve it’s own stress within its own width, therefore not transferring it to the other tyre? Or would it be worse because the outer tyre could create more “leverage “?

Sorry, I’m not sure I’m using the right terms, I never was much good at physics.

It seems to me that I could get much more rubber under a truck by using the widest possible tyre on the front and fitting duals on the rear. That way, I could make it use up every mm of the maximum legal road width of 3 metres.

There are lots of dual equipped trucks on the internet but they’re not up to 3 metres wide, which to me seems a waste. Perhaps the half shaft problem is the limiting factor?

Most folks say duals aren’t ideal in our damp climate because of mud build up between them, but on dualled quarry trucks I used to see a vertical steel bar hanging between the dual rear tyres to dislodge rocks and I wonder whether something similar could be fitted to stop mud build up? Maybe with really stiff brushes too, to keep things really clean?

If the converted truck had hub reduction axles the risk of snapped half shafts would be much less.

 

[Cab-over Pete]

The least stress will be when the mounting dish is in the centre of the rim

I suppose that makes sense. I said I’m not very good with physics!

The Big A rims have Central dishes and dual wheels would, in effect, be the same.

 

[davedb]

If the converted truck had hub reduction axles the risk of snapped half shafts would be much less.

Would a stretched double drive tractor unit be an option I wounder, put some good big wheels on it and stick a body on

 

[powerfarmer]

Would a stretched double drive tractor unit be an option I wounder, put some good big wheels on it and stick a body on

It'd be worth trying, wouldn't cost the earth to make up, but making it road legal might be difficult.

 

[Shovelhands]

I suppose that makes sense. I said I’m not very good with physics!

The Big A rims have Central dishes and dual wheels would, in effect, be the same.

Only if your duals are central, to achieve the kind of width that you want, the rims will have to be offset I’d imagine, so the outside one went out more than the inside moved in. I don’t think I’ve explained that well enough

Thinking outside the box for a moment, Pete, do you actually ‘need’ a 4wd truck? Many of the American truck based units are not 4wd. You yourself have coped for many years with a vehicle that’s not 4wd and doesn’t even have diff lock. I know your terrain is possibly different from mine, and that of many of the American units will encounter. But , could you start with a standard rigid unit, nice cab, big engine.... and take the back axle off, put an Allison auto in it, if you couldn’t find an auto truck, then fit a nice big axle on the back, as we’ve discussed before, something like a Volvo ADT axle would possibly suit nicely, Big hub reductions, you’d not break them in a hurry, diff lock for those moments when you ‘need’ it. Then fit the widest rubber possible to the back. I suppose there is the possibility of altering the chassis width to accommodate really decent rear rubber, almost Big A size rubber! Then jam as much as you could under the front, no need to worry about matching front and rear, as there no front drive.
This could be a project you can develop over time, while still running your other kit, keeping the Multidrive for the jobs it’s most comfortable on and then having the truck based unit for work that will suit it best.

Just a thought......

 

[MB Trac]

I know of a guy that built a spreader on one of the smaller Samils. Available in 4x4 and 6x6. Ex - military.

 

[Cab-over Pete]

They look useful little trucks.

@Shovelhands if you had asked 5 years ago I wouldnt have worried about 4 wd but since using the Multidrive it is handy on banks and slippery gateways etc. You know with the Big A occasionally you turn and she decides to keep going straight!!

It’s all good stuff to think about I suppose!!

 

[davedb]

They look useful little trucks.

@Shovelhands if you had asked 5 years ago I wouldnt have worried about 4 wd but since using the Multidrive it is handy on banks and slippery gateways etc. You know with the Big A occasionally you turn and she decides to keep going straight!!

It’s all good stuff to think about I suppose!!

A double rear drive would solve most of that tho apart from the turning I suppose

 

[powerfarmer]

Only if your duals are central, to achieve the kind of width that you want, the rims will have to be offset I’d imagine, so the outside one went out more than the inside moved in. I don’t think I’ve explained that well enough

Thinking outside the box for a moment, Pete, do you actually ‘need’ a 4wd truck? Many of the American truck based units are not 4wd. You yourself have coped for many years with a vehicle that’s not 4wd and doesn’t even have diff lock. I know your terrain is possibly different from mine, and that of many of the American units will encounter. But , could you start with a standard rigid unit, nice cab, big engine.... and take the back axle off, put an Allison auto in it, if you couldn’t find an auto truck, then fit a nice big axle on the back, as we’ve discussed before, something like a Volvo ADT axle would possibly suit nicely, Big hub reductions, you’d not break them in a hurry, diff lock for those moments when you ‘need’ it. Then fit the widest rubber possible to the back. I suppose there is the possibility of altering the chassis width to accommodate really decent rear rubber, almost Big A size rubber! Then jam as much as you could under the front, no need to worry about matching front and rear, as there no front drive.
This could be a project you can develop over time, while still running your other kit, keeping the Multidrive for the jobs it’s most comfortable on and then having the truck based unit for work that will suit it best.

Just a thought......

A Bin wagon ! Most of the older ones have Allison auto boxes and double drive hub reduction, Cummins engine too

 

[powerfarmer]

 

[Will 1594]

Only if your duals are central, to achieve the kind of width that you want, the rims will have to be offset I’d imagine, so the outside one went out more than the inside moved in. I don’t think I’ve explained that well enough

Thinking outside the box for a moment, Pete, do you actually ‘need’ a 4wd truck? Many of the American truck based units are not 4wd. You yourself have coped for many years with a vehicle that’s not 4wd and doesn’t even have diff lock. I know your terrain is possibly different from mine, and that of many of the American units will encounter. But , could you start with a standard rigid unit, nice cab, big engine.... and take the back axle off, put an Allison auto in it, if you couldn’t find an auto truck, then fit a nice big axle on the back, as we’ve discussed before, something like a Volvo ADT axle would possibly suit nicely, Big hub reductions, you’d not break them in a hurry, diff lock for those moments when you ‘need’ it. Then fit the widest rubber possible to the back. I suppose there is the possibility of altering the chassis width to accommodate really decent rear rubber, almost Big A size rubber! Then jam as much as you could under the front, no need to worry about matching front and rear, as there no front drive.
This could be a project you can develop over time, while still running your other kit, keeping the Multidrive for the jobs it’s most comfortable on and then having the truck based unit for work that will suit it best.

Just a thought......

Joskins cargo trac Is what you need

 

[Shovelhands]

They look useful little trucks.

@Shovelhands if you had asked 5 years ago I wouldnt have worried about 4 wd but since using the Multidrive it is handy on banks and slippery gateways etc. You know with the Big A occasionally you turn and she decides to keep going straight!!

It’s all good stuff to think about I suppose!!

Yes I can certainly see where your coming from. And as you say, there are times when an A would benefit from front drive, even diff lock, but for me those times are few and far between. Although this year was the closest I’ve ever come to getting one ‘set’ while pushing my luck a bit too far in one field!, and in another innocent looking spot on a headland, while turning, the outside wheel went in so deep that I thought I was a gonna! Thankfully, a heavy right foot, and a firm grip of the seat foam, kept me going...just!

Sorry, I digress......

Back on topic.....

Could the truck, with just rear drive, be more of another string to your bow, so to speak, rather than a total solution for every event. As we are discovering with this thread, there doesn’t seem to be a complete solution, no matter how big the budget, there are drawbacks with everything. Rather than a replacement for the Multidrive, could you just add to the fleet, to give greater flexibility? The modified truck would be a do-able extra ‘string’, on a modest budget, rather than a big purchase on a new machine, with all your hopes and dreams wrapped up in one package?....

 

[Cab-over Pete]

I like that idea a lot.

 

[Deutz631]

http://www.bruhns-karstaedt.de/?cid=1480957868&name=Arocs+mit+Rauch+Streuer+als+Illustration

http://www.bruhns-karstaedt.de/?cid=1456731215&name=Arocs+im+Einsatz
Or a bruhns Mercedes Arocs agri build.

http://www.bruhns-karstaedt.de/?cid=1364221207&name=Secutor+mit+Düngerstreuer
http://www.bruhns-karstaedt.de/?cid=1364221207&name=Secutor+mit+Düngerstreuer
Secutor

 

[Andrew]

Pete, are you (or anyone else for that matter) coming to the NAAC Contractor event on 14th December at Peterborough showground? There will be people there who know all the ins and outs of stretching Fastracs / piggyback spreaders with an extra axle / importing kit from USA. Could be a worthwhile day out for you.

 

[Cab-over Pete]

I am thinking about it but I have somewhere else I really need to be that day. Im trying to get it changed if I can.