Front axle question?

[dodge man]

I was watching the videos of the roll overs on the saftey forum. I noticed that the fact that the front axle pivots can contribute to a roll over. So why do the front axles pivot on a tractor? I'm sure there is a good reason.

 

[brandoro]

If the front axle didn't pivot you would only have all four wheels planted when you were on very level ground.

 

[N80]

It seems to me the pivoting front axle helps prevent rollovers.

 

[Shmudda]

N80.....

Actually the piviot actually enables roll overs if the front bucket is loaded unevenly.....

Been there rolled that........

Craig

 

[N80]

N80.....

Actually the piviot actually enables roll overs if the front bucket is loaded unevenly.....


Craig

How so?

 

[dodge man]

In my mind the pivot can contribute when the tractor starts tip a little on the front axle, it gets the momentum going in the direction it wants to tip over. I would think a uneven load in the bucket would make it worse. It's just me thinking out loud, I don't really know.

 

[rbargeron]

...... So why do the front axles pivot on a tractor?.......

When tractors were developed for flat-land farming they had two front wheels mounted very close together - hence the "tricycle" designation for these narrow-front machines. They were great in fields of roqw crops - especially with adjustable rear width wheels that slid in and out on the axles to match the row spacing. But they were really dangerous on slopes - very easy to tip one over when a rear wheel went up and over a rock too fast. Pretty soon the "wide front end" tractor style became more common - but teh rear axle was still fixed so there had to be some flexibility somewhere so all the wheels could be on the ground.

Evolution is slow. It makes more sense for a loader to be at the end where the fixed axle is - and New Holland has that on their double-ender. But the bulk of the tractor world is slow to change.

 

[N80]

In other words, if the front axle was fixed, anything that raised the rear right would also be prone to raise the front right? Thereby making tipping easier?

 

[rbargeron]

In other words, if the front axle was fixed, anything that raised the rear right would also be prone to raise the front right? Thereby making tipping easier?

If the front axle was fixed like the rear one, the tractor would spend a lot of time on three wheels and traction would suffer. It would be more tippy feeling - but would actually be somewhat less prone to tipping over because the range of pivot motion in front would be zero. With a load in the bucket there would be better support closer to the load.

Wheel loaders generally have fixed front axles, and pivoting rear axles - even with four equal size tires. Our little CUT's are designed more like farm tractors - though not many of us are farmers. Every feature is a marketing compromise - large wheels, small wheels, tracks, articulated, front implement, rear implement etc. etc.

Occasionally somebody come out with a "radical" design which just makes perfect mechanical sense - but it doesn't "look" like a regular tractor so market acceptance is slow - example: New Holland TV Bi-Directional.

 

[N80]

If the front axle was fixed like the rear one, the tractor would spend a lot of time on three wheels and traction would suffer. It would be more tippy feeling - but would actually be somewhat less prone to tipping over because the range of pivot motion in front would be zero.

That sounds like you are saying that front axles pivot so that we feel safer when we are actually less safe. But then again, traction is important in avoiding rollovers as well, in terms of steering in a 2wd and steering and traction in a 4wd.

Occasionally somebody come out with a "radical" design which just makes perfect mechanical sense - but it doesn't "look" like a regular tractor so market acceptance is slow - example: New Holland TV Bi-Directional.

I'm sure the looks put some people off but the complexity built into that machine (especially in regard to the operator station) would be enormous and expensive to. Not only that, but even though the typical CUT owner does not farm with it, most implements are designed for the 3 pt hitch and with that machine you'd have to remove the loader every time you want to hook up your finish mower.