Spacers - Front and Rear, or Rear Only?

Henro

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Closed mind? Do you mean the guy denying the math? This isn't about what we think or feel, it is physics and calculus. It is a shame you can't just come to the correct conclusion.

Ready for a real mind blowing?

Longer is more stable to.
NHSleddog, this is almost becoming comical...but...for the sake of discussion. Are you saying that a jeep acts exactly the same as a tractor with a center pivot front axle? (With or without spacers)

I feel you are exactly correct with respect to a Jeep or other similar type vehicle becoming more stable when spacers are added to the front OR the rear, or both.. But I think you are missing the point that the front axle on a tractor does little to add to stability until a travel stop is reached (aside from the weight lowering the center of gravity) .

I am really not trying to be argumentative. But the front axle cannot do anything to prevent the tractor from tilting sideways until a travel stop is reached.

Would you explain why you think (as you seem to) that the front axle affects stability when it is in its free state, and not at either travel stop?
 

ayak

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Not in a million years would I ever consider adding spacers to a pivoting front (to avoid wearing something prematurely) but I do suppose once it’s actually ‘at the stop’ (now pretending to be non-pivoting), I surmise wider would be better. But on a hillside about to tip, I’m probably rearranging the deck chairs on the Titanic at that point, worrying about it.
 
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NHSleddog

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NHSleddog, this is almost becoming comical...but...for the sake of discussion. Are you saying that a jeep acts exactly the same as a tractor with a center pivot front axle? (With or without spacers)

I feel you are exactly correct with respect to a Jeep or other similar type vehicle becoming more stable when spacers are added to the front OR the rear, or both.. But I think you are missing the point that the front axle on a tractor does little to add to stability until a travel stop is reached (aside from the weight lowering the center of gravity) .

I am really not trying to be argumentative. But the front axle cannot do anything to prevent the tractor from tilting sideways until a travel stop is reached.

Would you explain why you think (as you seem to) that the front axle affects stability when it is in its free state, and not at either travel stop?
This isn't what I think, this is math. I have no choice in it.

I have several thousand hours of successful tractoring over 30 years time, I am well aware that the front axle has a pivot.

Wider is more stable with a pivot and without.

Put the wheels 6" apart.

Put the wheels 10' apart.

Which one is easier to tip over? Not rock back and forth, tip over. Now roll up on a 3' object, the 6" set is already tipped over before you get on top of the object. The 10' set has a 20+deg incline - wider is AGAIN more stable. I can't actually think of a single scenario where wider is less stable.

If you wanted to get deep in the math, there is also the fact that you can't add width without also adding weight. So I'll just go ahead and make another bold statement,

More weight below the COG adds stability as well.

I have nothing to do with the physics involved.
 
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NHSleddog

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Not in a million years would I ever consider adding spacers to a pivoting front (to avoid wearing something prematurely) but I do suppose once it’s actually ‘at the stop’ (now pretending to be non-pivoting), I surmise wider would be better. But on a hillside about to tip, I’m probably rearranging the deck chairs on the Titanic at that point, worrying about it.
In my case they sell bigger tires and wheels for my model. Obviously the assembly was manufactured to handle more than how it was delivered.
 

Henro

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This isn't what I think, this is math. I have no choice in it.

I have several thousand hours of successful tractoring over 30 years time, I am well aware that the front axle has a pivot.

Wider is more stable with a pivot and without.

Put the wheels 6" apart.

Put the wheels 10' apart.

Which one is easier to tip over? Not rock back and forth, tip over. Now roll up on a 3' object, the 6" set is already tipped over before you get on top of the object. The 10' set has a 20+deg incline - wider is AGAIN more stable. I can't actually think of a single scenario where wider is less stable.

If you wanted to get deep in the math, there is also the fact that you can't add width without also adding weight. So I'll just go ahead and make another bold statement,

More weight below the COG adds stability as well.

I have nothing to do with the physics involved.
Thanks for giving some examples. I agree that weight of the front axle lowers the COG, as I stated above, but that is not the question being discussed.

Semantics may be at play here. I don’t think anyone has said wider is less stable. The point I have personally been making is front wheel width is basically irrelevant, until a front axle stop comes into play. And at that point it may be too late.

I assume you meant to drive over a 3’ object with one front wheel? Say the left wheel, for the sake of discussion.

That object can only cause the tractor to tilt to the right side, because it is lifting the left wheel. At some point (regardless of wheel spacing) the front axle stop on the left side is reached. At that point the front axle could help keep the tractor from tipping to the LEFT, but since the left front wheel is being lifted, the tractor has no tendency to tip to the left side.

At this point the front axle cannot do anything to keep the tractor from tipping to the right side, until the tractor starts to tip over (if it gets to that point). AND only once the front axle stop on the right side is reached.

Should that tractor have +/-15 degrees of front axle pivot motion, that means the tractor can move through 30 degrees of rotation BEFORE the front axle can have any affect on what is happening at all. By that time the effect, even with added wheel spacers, likely will not be enough to oppose the momentum of the tractors rotation.

Second example would be lifting a load with the loader, without enough ballast on the rear. With or without front spacers, unless the load is perfectly balanced, when the rear wheels come off the ground, the tractor will tilt to one side or the other. The front axle, whether the wheels are 5’ or 50’ apart can do nothing to inhibit this rotation UNTIL a travel limit stop is reached. At that point, wider is certainly better. But a couple inches wider on the front may not help much.
 
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NHSleddog

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Thanks for giving some examples. I agree that weight of the front axle lowers the COG, as I stated above, but that is not the question being discussed.

Semantics may be at play here. I don’t think anyone has said wider is less stable. The point I have personally been making is front wheel width is basically irrelevant, until a front axle stop comes into play. And at that point it may be too late.

I assume you meant to drive over a 3’ object with one front wheel? Say the left wheel, for the sake of discussion.

That object can only cause the tractor to tilt to the right side, because it is lifting the left wheel. At some point (regardless of wheel spacing) the front axle stop on the left side is reached. At that point the front axle could help keep the tractor from tipping to the LEFT, but since the left front wheel is being lifted, the tractor has no tendency to tip to the left side.

At this point the front axle cannot do anything to keep the tractor from tipping to the right side, until the tractor starts to tip over (if it gets to that point). AND only once the front axle stop on the right side is reached.

Should that tractor have +/-15 degrees of front axle pivot motion, that means the tractor can move through 30 degrees of rotation BEFORE the front axle can have any affect on what is happening at all. By that time the effect, even with added wheel spacers, likely will not be enough to oppose the momentum of the tractors rotation.

Second example would be lifting a load with the loader, without enough ballast on the rear. With or without front spacers, unless the load is perfectly balanced, when the rear wheels come off the ground, the tractor will tilt to one side or the other. The front axle, whether the wheels are 5’ or 50’ apart can do nothing to inhibit this rotation UNTIL a travel limit stop is reached. At that point, wider is certainly better. But a couple inches wider on the front may not help much.
It doesn't matter if it pivots in full circles, wider is more stable. You still don't get it but that is OK.

I will try to draw some pictures later when I have time. Maybe you will get it after seeing a picture. Although where you already accused me of spreading false information, I'm not holding my breath - SMH.
 

Henro

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It doesn't matter if it pivots in full circles, wider is more stable. You still don't get it but that is OK.

I will try to draw some pictures later when I have time. Maybe you will get it after seeing a picture. Although where you already accused me of spreading false information, I'm not holding my breath - SMH.
OK, I give up.

But please do respond to the two examples I gave above, and show how the front axle can have any effect to prevent tilting of the tractor, BEFORE a front axle stop is hit (Other than what it contributes to lower the center of gravity).

Without looking back I do not remember my exact words, but I guess that might have been an unfair thing to say...I believe when someone states something he believes ...that is all he he doing when he is sincere.

But I do think you will have difficulty proving that the front axle has any effect (other than what it contributes to lower the center of gravity) until an axle stop is reached.

I will keep an open mind though...for sure.

In the end, I think the question is simply which offers the greatest opportunity for protection:

1) Spacers on all four tractor wheels...or...

2) No spacers on the front, and wider spacers on the rear.

I believe option (2) is the better choice.

Let me add a PS: I know we could have moved this discussion to a private message, as it seems like only the two of us are discussing it, but I figured it might be of interest to others in the future if we kept the discussion public. (perhaps only a small chance of that...LOL)
 

Mike9

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If the manual says "no front spacers" then they mean "no front spacers". The problem with front spacers is if doing so voids your warranty and I believe they could figure out the cause of the failure.
 
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NHSleddog

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If the manual says "no front spacers" then they mean "no front spacers". The problem with front spacers is if doing so voids your warranty and I believe they could figure out the cause of the failure.
What manual are you talking about?

This is the only reference to front spacers in my manual (adding them).

spacer2.jpg
 
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NHSleddog

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OK, I give up.

But please do respond to the two examples I gave above, and show how the front axle can have any effect to prevent tilting of the tractor, BEFORE a front axle stop is hit (Other than what it contributes to lower the center of gravity).

Without looking back I do not remember my exact words, but I guess that might have been an unfair thing to say...I believe when someone states something he believes ...that is all he he doing when he is sincere.

But I do think you will have difficulty proving that the front axle has any effect (other than what it contributes to lower the center of gravity) until an axle stop is reached.

I will keep an open mind though...for sure.

In the end, I think the question is simply which offers the greatest opportunity for protection:

1) Spacers on all four tractor wheels...or...

2) No spacers on the front, and wider spacers on the rear.

I believe option (2) is the better choice.

Let me add a PS: I know we could have moved this discussion to a private message, as it seems like only the two of us are discussing it, but I figured it might be of interest to others in the future if we kept the discussion public. (perhaps only a small chance of that...LOL)
I give up too. You are right this is getting funny, but not for the reason you think.

Does traction add to stability?
Does friction add to stability?
Does weight add to stability?
Does angle effect stability?

Is your only reference to stability tipping the tractor completely over? It doesn't matter if that is all you go by, wider is still more stable but there is a lot more to it than just that.

Like I said above it is a math answer. Not a "what I think", I don't have a choice in it.

Visual-Math-Aid.jpg


Hand scale only but it is close.

One the axle is sitting at a 50+deg incline, the other is barely over 15deg.

This is an extreme example to show it visually however the math will prove it out for any width increase/decrease you use. Gravity is an equal constant regardless of angle.

I think you are just getting hung up on the pivot and the stops. Adding width will add to stability in every scenario I can think of regardless of the pivot and the stops.
 

Freeheeler

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You are right this is getting funny,
Funny or Fun? You guys remind me of myself and some buddies drinking beverages on the dock arguing about, well nothing, but doing it successfully for hours. At some point we'd switch sides and and try to prove the opposite point. Good times ;)
 

Henro

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Funny or Fun? You guys remind me of myself and some buddies drinking beverages on the dock arguing about, well nothing, but doing it successfully for hours. At some point we'd switch sides and and try to prove the opposite point. Good times ;)
I give up too. You are right this is getting funny, but not for the reason you think.

Does traction add to stability?
Does friction add to stability?
Does weight add to stability?
Does angle effect stability?

Is your only reference to stability tipping the tractor completely over? It doesn't matter if that is all you go by, wider is still more stable but there is a lot more to it than just that.

Like I said above it is a math answer. Not a "what I think", I don't have a choice in it.

View attachment 58625

Hand scale only but it is close.

One the axle is sitting at a 50+deg incline, the other is barely over 15deg.

This is an extreme example to show it visually however the math will prove it out for any width increase/decrease you use. Gravity is an equal constant regardless of angle.

I think you are just getting hung up on the pivot and the stops. Adding width will add to stability in every scenario I can think of regardless of the pivot and the stops.
Ha Ha, I can't seem to help myself...here goes another reply...

Does traction add to stability? I would think so. Bad situation less like to happen.
Does friction add to stability? I would think so. Bad situation less like to happen.
Does weight add to stability? ONLY if it lowers the center of gravity
Does angle effect stability? COG affects stability. Angle shifts COG in danger direction.

Now remember the thread title:
Spacers - Front and Rear, or Rear Only?

I have been attempting to reply to this question. This seems to have turned into a debate that concerns a much wider area than the specific question.

I have not disputed that wider is generally more stable. BUT I have given a specific example of how wider on the front axle with a center pivot has no affect on stability UNTIL one of the axle stops has been reached.

Claiming that math proves this wrong, without showing the math, does not prove much.

My honest understanding is that given the choice, putting wider spacers on the rear wheels will offer more to prevent a tractor roll over than putting spacers on the front and thinner spacers on the rear.

In my mind stability means keeping the tractor upright.

My question therefore is, NHSleddog, do you disagree with this? Do you feel that putting spacers on the front is wise, if it results in putting narrower spacers on the rear?

This is really what the OP asked in the thread title...

Freeheeler, need some help...I can't seem to find my glass of beer! :ROFLMAO:
 

bird dogger

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For the sake of friendly discussion and at the risk of personal injury by falling on my own sword…..I’ll enter the fray.:ROFLMAO:
1619119022203.png


I agree with NHS that technically speaking “wider is more stable”. His illustration above is a perfect example of what I was going to provide. Since he’s drawn the illustration…here’s the practical example of that. If you haven’t grown up on a farm or in farm country, you might not be familiar with the old narrow front tractors. Example: IH Farmall A, B, H, etc. Some had the narrow front with only 1 wheel or 2 (as in a “V” configuration). My uncle had both types.

Using the V type, if you hit a small rock, hidden stump, or more likely a solid gopher mound squarely with just one of the front wheels you were well aware and most likely now on two wheels turning into the lean to prevent going turtle. Or the reverse….drop one wheel into an unseen gopher or badger hole and you would suffer the same results. They were fixed axles of course, but it didn’t take much of a bump to get your attention. However, with a wide front (whether fixed or pivoting axle) that same small object under the front wheel would get your attention but certainly not to the same degree on the narrow front tractor with the “V” tire configuration. Wider is technically better for stability whether it’s a fixed or pivoting front. It doesn’t have to reach the “stop” to be called more stable.

But as NHS even alluded to there are caveats as to when that extra width is beneficially practical. Let’s call those caveats “costs”. Sure, it makes more sense to first add the extra width to the rear wheels, as in more “bang for the buck”. But if it didn’t make sense to also have a wider front wheel base we’d be limited to those one or two wheel narrow front tractors as mentioned. At some point with a wider front end for stability you start paying the extra costs in possibly more wear and tear, less maneuverability, more manufacturing costs, storing, shipping, etc. and one has to decide when the benefits for you do or don’t outweigh those costs. It’s always a trade off between everything as in more of one benefit, less of another. And that was (I think) NHS’s point that the blanket statement that wider wheel spacing on a pivoting front axle does absolutely no good is technically not correct. It’s a little short sighted. However, there is a point where the width becomes impractical because of all the caveats.

If one states that they would never, ever put wheel spacers on the font wheels, that person most likely hasn’t worked on a farm or at least never worked with row crops. Even adjustable front ends can’t meet all needs under every condition. The world is a bigger place than one’s own garden, truck farm, corporate farm, construction company, landscaping/snow removal business, etc. For those that can’t afford a different tractor for every different need there are accessories such as wheel spacers. Again, you have to decide the cost to benefit ratio for your certain circumstances.

More importantly, one very big factor not mentioned above whether you have a narrow front, wide front, pivoting axle, solid axle, etc. is ground speed! Even a slow ground speed which is safe in one condition can be deadly dangerous in another no matter what tractor configuration you have. Momentum can take you by surprise and be the major contributing factor in a rollover! Even on level ground, pivoting or fixed axle! And especially while using a loader.

I’ve had ancestors that have said nothing will replace the horse for the best mode of transportation. Man will certainly never be able to fly, especially under his own power. It’s physically impossible to break the sound barrier. No one will ever land on the moon.

I’ve learned to sparingly use the term “highly unlikely” because as soon as you say you’re absolutely correct or certain…..somebody will prove you wrong. As in saying, “it’s absolutely impossible that there will ever be a manmade rotorcraft making a powered flight on another planet…..especially Mars.” :ROFLMAO:
 

Henro

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For the sake of friendly discussion and at the risk of personal injury by falling on my own sword…..I’ll enter the fray.:ROFLMAO: View attachment 58643

I agree with NHS that technically speaking “wider is more stable”. His illustration above is a perfect example of what I was going to provide. Since he’s drawn the illustration…here’s the practical example of that. If you haven’t grown up on a farm or in farm country, you might not be familiar with the old narrow front tractors. Example: IH Farmall A, B, H, etc. Some had the narrow front with only 1 wheel or 2 (as in a “V” configuration). My uncle had both types.

Using the V type, if you hit a small rock, hidden stump, or more likely a solid gopher mound squarely with just one of the front wheels you were well aware and most likely now on two wheels turning into the lean to prevent going turtle. Or the reverse….drop one wheel into an unseen gopher or badger hole and you would suffer the same results. They were fixed axles of course, but it didn’t take much of a bump to get your attention. However, with a wide front (whether fixed or pivoting axle) that same small object under the front wheel would get your attention but certainly not to the same degree on the narrow front tractor with the “V” tire configuration. Wider is technically better for stability whether it’s a fixed or pivoting front. It doesn’t have to reach the “stop” to be called more stable.

But as NHS even alluded to there are caveats as to when that extra width is beneficially practical. Let’s call those caveats “costs”. Sure, it makes more sense to first add the extra width to the rear wheels, as in more “bang for the buck”. But if it didn’t make sense to also have a wider front wheel base we’d be limited to those one or two wheel narrow front tractors as mentioned. At some point with a wider front end for stability you start paying the extra costs in possibly more wear and tear, less maneuverability, more manufacturing costs, storing, shipping, etc. and one has to decide when the benefits for you do or don’t outweigh those costs. It’s always a trade off between everything as in more of one benefit, less of another. And that was (I think) NHS’s point that the blanket statement that wider wheel spacing on a pivoting front axle does absolutely no good is technically not correct. It’s a little short sighted. However, there is a point where the width becomes impractical because of all the caveats.

If one states that they would never, ever put wheel spacers on the font wheels, that person most likely hasn’t worked on a farm or at least never worked with row crops. Even adjustable front ends can’t meet all needs under every condition. The world is a bigger place than one’s own garden, truck farm, corporate farm, construction company, landscaping/snow removal business, etc. For those that can’t afford a different tractor for every different need there are accessories such as wheel spacers. Again, you have to decide the cost to benefit ratio for your certain circumstances.

More importantly, one very big factor not mentioned above whether you have a narrow front, wide front, pivoting axle, solid axle, etc. is ground speed! Even a slow ground speed which is safe in one condition can be deadly dangerous in another no matter what tractor configuration you have. Momentum can take you by surprise and be the major contributing factor in a rollover! Even on level ground, pivoting or fixed axle! And especially while using a loader.

I’ve had ancestors that have said nothing will replace the horse for the best mode of transportation. Man will certainly never be able to fly, especially under his own power. It’s physically impossible to break the sound barrier. No one will ever land on the moon.

I’ve learned to sparingly use the term “highly unlikely” because as soon as you say you’re absolutely correct or certain…..somebody will prove you wrong. As in saying, “it’s absolutely impossible that there will ever be a manmade rotorcraft making a powered flight on another planet…..especially Mars.” :ROFLMAO:
Thanks for your insight Bird Dogger.

So at the end of the day, would you say maximize the rear tire width with spacers before adding spacers to the front axle?

I think that was the OP's original question...

My logic/understanding is it is best to maximize the rear width before going to the front...if one wants to maximize the chances of keeping the tractor upright in a worst case situation.
 

NHSleddog

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I will attempt this one more time.

Front, rear, doesn't matter. One does not dictate the other.

Add to just the front, it will be more stable.
Add just to the rear, it will be more stable.
Add to the front and rear, it will be more stable.

The OP can do what he wants.

This rabbit hole started when someone said adding width to the front has no effect on stability. I was just saying that was wrong.

Did my picture help at all?
 

Freeheeler

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Anyone that has ever driven or ridden in a Pontiac Grand Prix knows that "wider is better". TV commercials don't lie.
 
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Henro

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I will attempt this one more time.

Front, rear, doesn't matter. One does not dictate the other.

Add to just the front, it will be more stable.
Add just to the rear, it will be more stable.
Add to the front and rear, it will be more stable.

The OP can do what he wants.

This rabbit hole started when someone said adding width to the front has no effect on stability. I was just saying that was wrong.

Did my picture help at all?
I agree this discussion has gone on long enough.

Thinking about it, I think we are on the same page, except that you feel the front axle center pivot can be ignored in the analysis, and I believe that the front axle only has an effect (other than its weight affecting COG) when an axle stop is reached.

Also agree that we can all do whatever we want.

Appreciate you taking the time to post the drawings. I agree with your drawings, common sense really. But in both cases the front axle would only raise the front of the tractor, and not add to stability if a axle stop were not reached.

Time to put this dog to sleep I think. :)
 
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bird dogger

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Thanks for your insight Bird Dogger.

So at the end of the day, would you say maximize the rear tire width with spacers before adding spacers to the front axle?

I think that was the OP's original question...

My logic/understanding is it is best to maximize the rear width before going to the front...if one wants to maximize the chances of keeping the tractor upright in a worst case situation.
Sorry for the delayed and long response but here goes my last thoughts (?) :) I've enjoyed the discussion and always open to change my mind when wrong and also to learn from other's opinion.

Of course, I absolutely agree that it’s more practical to first add width to the rear axle if at all possible. But the OP first asked if both front and rear tires needed to be in line with each other. He also simply asked for the pros and cons of spacers in both locations. Hence the disagreement over the blanket statement offered that adding spacers on the front pivoting axle had no affect on stability.

I think your interpretation of stability for you is much narrower that NHS’s, mine, and possibly others. I view stability as a variable that can range from completely stable (a tractor at rest on level ground), very stable (safe operating practices under the given conditions whether on level or inclined ground), to extremely unstable (unsafe operation that can easily lead to a rollover or accident, whether on level or inclined ground). It really wouldn’t have to end in a rollover to be considered unstable. (Which seems to be our main point of contention.) Example: Isn’t it considered unstable if the ride would become so bumpy that the operator loses control and strikes an object causing damage and injuries to the tractor, himself, and/or others? And the range from very stable to extremely unstable can be wide to very narrow depending on each tractor’s configuration, operating speed, skill of the operator, common sense, and more.

In a way, you even agree with us in some of your earlier statements. Think of it this way and using just a bare tractor as an example (no loader, no attachments):

A tractor with a very solid narrow front fixed axle hitting a small object under one front wheel will tilt the whole tractor to an extreme angle if the speed was excessive enough where both wheels on that side would leave the ground before rocking back and forth between opposite tires front to back. There is momentum at play here because of the unsafe speed.

Now, the same tractor with a much wider front hits the same small object at speed but because the angle of tilt is much less (as in NHS’s drawing). Less tilt at the same speed equals greater stability and a less chance of rollover.

Now take the same tractor with a narrow pivoting front axle and hit that same small object and the tractor may hit the pivot stop (or not) but any tilt wouldn’t be quite as extreme as with the solid axle. Maybe not much less but still it would be less. (Geometry is the more technical math description for the reason). Now with a wide front pivoting axle chances are much greater that it would not hit the pivot stop at all, the rear wheel is still on the ground till it strikes the same smaller rock. Only one rear wheel off the ground now and less momentum built up that could lead to a roll over. Thus, more stability.

Another way to look at it: Think of the pivoting front axle as a kind of shock absorber. If front and back wheels are in line it might be only the back wheel striking the same small obstacle that will cause the tractor to tilt. If two equally small objects spaced in line at the exact wheelbase (front to rear) were struck at the same time then again, possibly only the rear tire would cause the tractor to tilt. If the wheels were not in line and only the front wheel hits the small object, then without the front axle hitting the pivot stop, the tractor wouldn’t tilt at all. The pivoting front axle therefore does improve stability and the wider the stance the better. Again, speed, momentum, safe operating under the conditions, etc. all contribute as much to the stability. And the pivoting front axle acting as a kind of a shock absorber can help to keep your tractor from tilting whether it hits the stop or not. Thus, it’s more stable. And consider small rocks on one side with a rut on the other. Double trouble for a fixed axle. Not so much for a pivoting axle depending on the sizes. But still......less.

You stated earlier above that with the pivoting axle hitting a smaller object you might not feel it at all unless the axle hits the stop. With a fixed axle you would. That goes along with what we are saying. Wider is better in all cases until practicality and those other costs dictate otherwise. But just as the range of stability can be very narrow, so can the range of practicality over the width of the front pivoting axle. But the blanket statement that adding to the width doesn’t matter on that axle is technically not correct in and of itself. IMHO, of course.

If a person were operating on only flat, level ground or on completely smooth inclined ground you may not agree. If you add rocks, bumps, pitted cow pasture, badger holes, hidden cut off stumps, or any unseen objects to that same terrain I think that person would agree that a wider front, pivoting axle smoothens the ride which helps to maintain control by adding to the stability. And if you’re cruising home in road gear at the end of the day on a smooth country road and didn’t notice that gopher mound or small rock……it would help convince you even more. Daylight between your pants and the tractor seat was fun when I was young and fearless. Now it can be quite scary. But less daylight between is certainly better, no matter how small the difference.

Just another thought: If a pivoting front axle doesn’t aid in stability until it reaches its stops: Then what is the function? Wouldn’t a tractor’s 3 basic goals be power, traction and stability? I’ll have to think more on that one.

If the responses had been something like, “For most practical reasons, it’s much better to add rear spacers first before considering the front spacers”, we likely wouldn’t have had this interesting discussion. But this has been a good, civil and fun discussion. Even just for safety’s sake, it will give people pause to consider all the reasons and what ifs. I’ve appreciated the discussion and respect everyone’s views. Thanks to all!
 
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Henro

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B2910, BX2200, KX41-2V mini Ex.
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Sorry for the delayed and long response but here goes my last thoughts (?) :) I've enjoyed the discussion and always open to change my when wrong and also to learn from other's opinion.

Of course, I absolutely agree that it’s more practical to first add width to the rear axle if at all possible. But the OP first asked if both front and rear tires needed to be in line with each other. He also simply asked for the pros and cons of spacers in both locations. Hence the disagreement over the blanket statement offered that adding spacers on the front pivoting axle had no affect on stability.

I think your interpretation of stability for you is much narrower that NHS’s, mine, and possibly others. I view stability as a variable that can range from completely stable (a tractor at rest on level ground), very stable (safe operating practices under the given conditions whether on level or inclined ground), to extremely unstable (unsafe operation that can easily lead to a rollover or accident, whether on level or inclined ground). It really wouldn’t have to end in a rollover to be considered unstable. (Which seems to be our main point of contention.) Example: Isn’t it considered unstable if the ride would become so bumpy that the operator loses control and strikes an object causing damage and injuries to the tractor, himself, and/or others? And the range from very stable to extremely unstable can be wide to very narrow depending on each tractor’s configuration, operating speed, skill of the operator, common sense, and more.

In a way, you even agree with us in some of your earlier statements. Think of it this way and using just a bare tractor as an example (no loader, no attachments):

A tractor with a very solid narrow front fixed axle hitting a small object under one front wheel will tilt the whole tractor to an extreme angle if the speed was excessive enough where both wheels on that side would leave the ground before rocking back and forth between opposite tires front to back. There is momentum at play here because of the unsafe speed.

Now, the same tractor with a much wider front hits the same small object at speed but because the angle of tilt is much less (as in NHS’s drawing). Less tilt at the same speed equals greater stability and a less chance of rollover.

Now take the same tractor with a narrow pivoting front axle and hit that same small object and the tractor may hit the pivot stop (or not) but any tilt wouldn’t be quite as extreme as with the solid axle. Maybe not much less but still it would be less. (Geometry is the more technical math description for the reason). Now with a wide front pivoting axle chances are much greater that it would not hit the pivot stop at all, the rear wheel is still on the ground till it strikes the same smaller rock. Only one rear wheel off the ground now and less momentum built up that could lead to a roll over. Thus, more stability.

Another way to look at it: Think of the pivoting front axle as a kind of shock absorber. If front and back wheels are in line it might be only the back wheel striking the same small obstacle that will cause the tractor to tilt. If two equally small objects spaced in line at the exact wheelbase (front to rear) were struck at the same time then again, possibly only the rear tire would cause the tractor to tilt. If the wheels were not in line and only the front wheel hits the small object, then without the front axle hitting the pivot stop, the tractor wouldn’t tilt at all. The pivoting front axle therefore does improve stability and the wider the stance the better. Again, speed, momentum, safe operating under the conditions, etc. all contribute as much to the stability. And the pivoting front axle acting as a kind of a shock absorber can help to keep your tractor from tilting whether it hits the stop or not. Thus, it’s more stable. And consider small rocks on one side with a rut on the other. Double trouble for a fixed axle. Not so much for a pivoting axle depending on the sizes. But still......less.

You stated earlier above that with the pivoting axle hitting a smaller object you might not feel it at all unless the axle hits the stop. With a fixed axle you would. That goes along with what we are saying. Wider is better in all cases until practicality and those other costs dictate otherwise. But just as the range of stability can be very narrow, so can the range of practicality over the width of the front pivoting axle. But the blanket statement that adding to the width doesn’t matter on that axle is technically not correct in and of itself. IMHO, of course.

If a person were operating on only flat, level ground or on completely smooth inclined ground you may not agree. If you add rocks, bumps, pitted cow pasture, badger holes, hidden cut off stumps, or any unseen objects to that same terrain I think that person would agree that a wider front, pivoting axle smoothens the ride which helps to maintain control by adding to the stability. And if you’re cruising home in road gear at the end of the day on a smooth country road and didn’t notice that gopher mound or small rock……it would help convince you even more. Daylight between your pants and the tractor seat was fun when I was young and fearless. Now it can be quite scary. But less daylight between is certainly better, no matter how small the difference.

Just another thought: If a pivoting front axle doesn’t aid in stability until it reaches its stops: Then what is the function? Wouldn’t a tractor’s 3 basic goals be power, traction and stability? I’ll have to think more on that one.

If the responses had been something like, “For most practical reasons, it’s much better to add rear spacers first before considering the front spacers”, we likely wouldn’t have had this interesting discussion. But this has been a good, civil and fun discussion. Even just for safety’s sake, it will give people pause to consider all the reasons and what ifs. I’ve appreciated the discussion and respect everyone’s views. Thanks to all!
I guess having tipped my tractor on the side once, I may be overly sensitive. In my mind stability equals ability to keep the tractor upright when things go bad.

I wish we all could sit down around a table and discuss this, as it does interest me also. And doing so face to face is SO MUCH better than using the written word, and easier too! In my case, I never meant to say that spacers on the front can never help. Simply that they only will help after a front axle stop is reached, while rear spacers help all the time.

That is a great point about what the purpose of a front axle with a center pivot really is! I have never thought about it, just took it as the way things are. Almost sounds like a question for another thread...I may actually ask that question and see what responses come. Never thought to ask it myself.

What I tried to say earlier, was that if a pivoting front axle rises over something on one side, the front of the tractor will lift up, but the tractor generally will not tilt. Something will certainly be felt when the front goes up...

Just for the record, I said that width on the front only comes into play when an axle stop is reached. I never meant to imply that width played no part in stability after an axle stop is reached. My bad if I was not clear in what I wrote...
 

NHSleddog

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B2650
Dec 19, 2019
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Southern, NH
I guess having tipped my tractor on the side once, I may be overly sensitive. In my mind stability equals ability to keep the tractor upright when things go bad.

I wish we all could sit down around a table and discuss this, as it does interest me also. And doing so face to face is SO MUCH better than using the written word, and easier too! In my case, I never meant to say that spacers on the front can never help. Simply that they only will help after a front axle stop is reached, while rear spacers help all the time.

That is a great point about what the purpose of a front axle with a center pivot really is! I have never thought about it, just took it as the way things are. Almost sounds like a question for another thread...I may actually ask that question and see what responses come. Never thought to ask it myself.

What I tried to say earlier, was that if a pivoting front axle rises over something on one side, the front of the tractor will lift up, but the tractor generally will not tilt. Something will certainly be felt when the front goes up...

Just for the record, I said that width on the front only comes into play when an axle stop is reached. I never meant to imply that width played no part in stability after an axle stop is reached. My bad if I was not clear in what I wrote...
You still don't get it but that is OK.

EVEN inside the tippping axis of the axle wider IS STILL MORE STABLE (not less or equal, but more) and certainly at the stops. In the "it must tip all the way over scenario", I hope some day the lightbulb goes off and you realize the wider you get the harder it is to get to the stops, ie the harder it is to tip over, ie it is more stable.