6" Wheel Spacers. What's likely to break?

[Henro]

I am still thinking about wheel spacers and new chains.

Was almost settled on 4" spacers, Tipped the B2910 on its side once ten years ago. Would rather not repeat that.

So I am wondering what might fail if I went to the full 6" spacer on each side. The goal is maximum side slope stability. I just need 1" spacers for chain clearance I think.

My 2 link ladder chains on the rear R4 tires suck, as they mostly fall between the lugs. Thinking of buying a different style, I think called euro style.

Also decided that I will buy chains for the front tires too. Will take the front chains off in spring, but leave the rear chains on year round. No pavement involved with my tractor use.

So if something would break, due to the increased stress caused by the 6" spacers, what would it likely be?

Whatever it is, better that than my neck!

Still, would rather break nothing...but willing to take the chance to save breaking something that is part of me...

What might likely fail? Axles, bearing, or worst case, the transmission housing itself?

No clue here...

 

[SDT]

I am still thinking about wheel spacers and new chains.

Was almost settled on 4" spacers, Tipped the B2910 on its side once ten years ago. Would rather not repeat that.

So I am wondering what might fail if I went to the full 6" spacer on each side. The goal is maximum side slope stability. I just need 1" spacers for chain clearance I think.

My 2 link ladder chains on the rear R4 tires suck, as they mostly fall between the lugs. Thinking of buying a different style, I think called euro style.

Also decided that I will buy chains for the front tires too. Will take the front chains off in spring, but leave the rear chains on year round. No pavement involved with my tractor use.

So if something would break, due to the increased stress caused by the 6" spacers, what would it likely be?

Whatever it is, better that than my neck!

Still, would rather break nothing...but willing to take the chance to save breaking something that is part of me...

What might likely fail? Axles, bearing, or worst case, the transmission housing itself?

No clue here...

No way to know with certainty but I would suspect transaxle axle bearing trunnions.

SDT

 

[NCL4701]

Some tractors are designed to have the wheels moved out 6”; some not so much. For example, if I wanted to move the wheels out 6” on the H, jack up one side, loosen the clamps, enlist the assistance of the 16lb sledge in persuading it to move, tighten the clamps. It’s designed to be run that way so there’s a reasonable expectation that the engineers designed the axle housing and bearings and axle shaft to handle that load. However, it didn’t come with a 3 point hitch so I’d be a bit hesitant to run it with the wheels all the way out with something heavy on the aftermarket 3 point. Probably wouldn’t skid logs raising the end of the log with the 3 point and wheels all the way out. Just pulling a couple of moldboard plows or a cultivator, shouldn’t be an issue.

Point being, what are the specs for maximum wheel spacers on your tractor? Certainly owners run spacers with no ill effects, but what is the limit? 6” is a long way when considering the additional load on the bearings and carrier created by the additional torque of the more distant wheel. Unless you can find someone who has put many hours on a machine like yours running 6” spacers it’s a crapshoot if something will fail, what will fail, or when it will fail. If you can’t find that person, checking with your dealer or Kubota corporate might be advisable.

 

[85Hokie]

The stress is not at the wheel or spacer - rather at the axle where it meets the case.

If you "pucker factor radar" is not tuned enough - get some 3" spaces and a slope finder

 

[GreensvilleJay]

re: The goal is maximum side slope stability.

you mean you won't be driving straight up and down the hill ??
If so NEVER a good,safe idea,though you should already know that

It boils down to how big an area you're talking about, number of times you're on teh slope and how deep your wallet is.
Old skool 'roads dept' put smaller diameter tires on the up hill side of tractors
New skool is they pivot them and combines.....
pretty sure if you hit a gopher hole, you'll know real fast what breaks !

 

[Henro]

View attachment 74619
Some tractors are designed to have the wheels moved out 6”; some not so much. For example, if I wanted to move the wheels out 6” on the H, jack up one side, loosen the clamps, enlist the assistance of the 16lb sledge in persuading it to move, tighten the clamps. It’s designed to be run that way so there’s a reasonable expectation that the engineers designed the axle housing and bearings and axle shaft to handle that load. However, it didn’t come with a 3 point hitch so I’d be a bit hesitant to run it with the wheels all the way out with something heavy on the aftermarket 3 point. Probably wouldn’t skid logs raising the end of the log with the 3 point and wheels all the way out. Just pulling a couple of moldboard plows or a cultivator, shouldn’t be an issue.

Point being, what are the specs for maximum wheel spacers on your tractor? Certainly owners run spacers with no ill effects, but what is the limit? 6” is a long way when considering the additional load on the bearings and carrier created by the additional torque of the more distant wheel. Unless you can find someone who has put many hours on a machine like yours running 6” spacers it’s a crapshoot if something will fail, what will fail, or when it will fail. If you can’t find that person, checking with your dealer or Kubota corporate might be advisable.

All points well taken.

My problem is that I am 75 this month, and heal quite slower than my tractor would if it failed. PLUS even with pretty good insurance, the tractor repair might be cheaper! LOL but reality too.

So I am just trying to get a gut feeling for how much I might be risking as far as tractor damage goes should I do what I think makes most sense for me at the expense of possible tractor damage.

I really do appreciate any guidance and advice members here give. I learned long ago that whatever I might think can often use readjustment.

 

[Henro]

re: The goal is maximum side slope stability.

you mean you won't be driving straight up and down the hill ??
If so NEVER a good,safe idea,though you should already know that

Yes, unfortunately, I live in the real world. LOL

Been a while since I have visited Ontario. Do you have hills there? Sorry, I don't remember...always like visiting Canada though...

 

[Henro]

The stress is not at the wheel or spacer - rather at the axle where it meets the case.

I realize that, thus the question...

Edit: the question was related to where the likely failure point might be. Axle itself, the bearings or the housing holding the bearings, or something else I am not considering...

 

[TheOldHokie]

I realize that, thus the question...

Edit: the question was related to where the likely failure point might be. Axle itself, the bearings or the housing holding the bearings, or something else I am not considering...

Nobody other than a design engineer at Kubota can reliably answer that question. They are the ones with the FEA calcs that went into the design. As has been suggested - take the maximum tread width adjustment provided by the adjustable tires and wheels and use that as your safe design limit. Six inches per side is a lot and with R4's and spacers you will not be starting at the narrowest setting.

Dan

 

[19thSF]

I am still thinking about wheel spacers and new chains.

Was almost settled on 4" spacers, Tipped the B2910 on its side once ten years ago. Would rather not repeat that.

So I am wondering what might fail if I went to the full 6" spacer on each side. The goal is maximum side slope stability. I just need 1" spacers for chain clearance I think.

My 2 link ladder chains on the rear R4 tires suck, as they mostly fall between the lugs. Thinking of buying a different style, I think called euro style.

Also decided that I will buy chains for the front tires too. Will take the front chains off in spring, but leave the rear chains on year round. No pavement involved with my tractor use.

So if something would break, due to the increased stress caused by the 6" spacers, what would it likely be?

Whatever it is, better that than my neck!

Still, would rather break nothing...but willing to take the chance to save breaking something that is part of me...

What might likely fail? Axles, bearing, or worst case, the transmission housing itself?

No clue here...

Just a thought. Moving the wheel out that far from the axle shaft creates a cantilevered load.

I am still thinking about wheel spacers and new chains.

Was almost settled on 4" spacers, Tipped the B2910 on its side once ten years ago. Would rather not repeat that.

So I am wondering what might fail if I went to the full 6" spacer on each side. The goal is maximum side slope stability. I just need 1" spacers for chain clearance I think.

My 2 link ladder chains on the rear R4 tires suck, as they mostly fall between the lugs. Thinking of buying a different style, I think called euro style.

Also decided that I will buy chains for the front tires too. Will take the front chains off in spring, but leave the rear chains on year round. No pavement involved with my tractor use.

So if something would break, due to the increased stress caused by the 6" spacers, what would it likely be?

Whatever it is, better that than my neck!

Still, would rather break nothing...but willing to take the chance to save breaking something that is part of me...

What might likely fail? Axles, bearing, or worst case, the transmission housing itself?

No clue here...

Hello Henro,

I guess that the design engineers could provide a detailed scientific explanation, but looking at it as a common sense answer..............................................the bearings (part 060) will have a shortened life, and when they fail, the oil seal (070) is likely to fail. How much shorter a life? Who knows, only time will tell. There are several people offering 6" spacers for sale. I guess that they wouldn't be selling many if you put them on, and the following week the hub sheered off the axle when you hit a bump.

If you put them on, let us know how you make out after some time has passed. We will all know the answer then.

Good luck with it!

 

[Henro]

Nobody other than a design engineer at Kubota can reliably answer that question. They are the ones with the FEA calcs that went into the design. As has been suggested - take the maximum tread width adjustment provided by the adjustable tires and wheels and use that as your safe design limit. Six inches per side is a lot and with R4's and spacers you will not be starting at the narrowest setting.

Dan

I guess this is likely true.

But that can be said for every question too.

With R4s on my B2910 there is no adjustable spacing option.

And I do not think with the B2910 even R1 tires would have an adjustable spacing option, but do not know.

So maybe it just comes down to, do what you will and take the chances?

That could be. But I was just asking for opinions of others that might have more experience than I do.

I keep remembering that Kubota says to remove the liquid ballast from my tires before using my backhoe...LOL...really?

Takes the wind out of my sails when considering asking them anything. Because I know the answer in advance. Don't do it.

But people do...as a matter of survival.

 

[Henro]

Just a thought. Moving the wheel out that far from the axle shaft creates a cantilevered load.

Hello Henro,

I guess that the design engineers could provide a detailed scientific explanation, but looking at it as a common sense answer..............................................the bearings (part 030) will have a shortened life, and when they fail, the oil seal (070) is likely to fail. How much shorter a life? Who knows, only time will tell. There are several people offering 6" spacers for sale. I guess that they wouldn't be selling many if you put them on, and the following week the hub sheered off the axle when you hit a bump.

If you put them on, let us know how you make out after some time has passed. We will all know the answer then.

Good luck with it!

View attachment 74626

Thanks for the reply. For some reason when I clicked on the link it did not work, but I see you image as part of your post.

Interestingly, I remember reading a post somewhere that said the likely bearing to fail was the one on the inside, #30 in your image, rather than #60.

I think this was because #60 was a pivot point. Don't know, but interesting non the less.

Just something I remember and have not resolved in my mind...

 

[Henro]

Just a thought. Moving the wheel out that far from the axle shaft creates a cantilevered load.

Hello Henro,

I guess that the design engineers could provide a detailed scientific explanation, but looking at it as a common sense answer..............................................the bearings (part 060) will have a shortened life, and when they fail, the oil seal (070) is likely to fail. How much shorter a life? Who knows, only time will tell. There are several people offering 6" spacers for sale. I guess that they wouldn't be selling many if you put them on, and the following week the hub sheered off the axle when you hit a bump.

If you put them on, let us know how you make out after some time has passed. We will all know the answer then.

Good luck with it!

View attachment 74626

Replying a second time...lost the first it looks like...

I recall in the past reading somewhere that the internal bearing was the one that experienced the most stress if wheel spacers were installed. That would be #30 in the drawing, rather than #60.

I think due to the pivoting action of #60.

More than this I do not know.

Still, while curious, I still value my neck more highly that the tractor drive train. LOL

Edit: I now see my previous attempt at replying. I think both are still valid though...

 

[North Idaho Wolfman]

From what I've experienced, as long as you don't have a BH or any heavy 3 point Implement and your not trying to run a Off road obstacle course with it, you should be ok with 6" of width.

All the one's I've repaired was not due to width but from abuse.
Don't hit trees, Big rocks, and Buildings!

 

[Henro]

From what I've experienced, as long as you don't have a BH or any heavy 3 point Implement and your not trying to run a Off road obstacle course with it, you should be ok with 6" of width.

All the one's I've repaired was not due to width but from abuse.
Don't hit trees, Big rocks, and Buildings!

I do have a backhoe, but do not use it that much, I mean it is not on there all the time.. I bought a mini ex that has about the same capability and like it better all around, although a bit larger mini ex probably would have been better.

Mostly I am interested in stability and using the rear blade for snow removal on sloped surfaces. Possibly when using the brush hog too, but that is rarely needed now. Of course, I do use the tractor for other things, like loader work and moving debris with the loader...so stability on side slopes is important for all the miscellaneous stuff we all do.

I think if I decide to do something it will be 6" spacers. Just putting value on my neck vs the tractor...

 

[85Hokie]

I do have a backhoe, but do not use it that much, I mean it is not on there all the time.. I bought a mini ex that has about the same capability and like it better all around, although a bit larger mini ex probably would have been better.

Mostly I am interested in stability and using the rear blade for snow removal on sloped surfaces. Possibly when using the brush hog too, but that is rarely needed now. Of course, I do use the tractor for other things, like loader work and moving debris with the loader...so stability on side slopes is important for all the miscellaneous stuff we all do.

I think if I decide to do something it will be 6" spacers. Just putting value on my neck vs the tractor...

Your rear tires loaded? If you said so earlier.... I missed it...... that in itself will be a huge help.

 

[lynnmor]

Of course there will be added stress to the downhill axle and if it snaps it will be a wild ride, possibily worse that just a tip over.

 

[NCL4701]

All points well taken.

My problem is that I am 75 this month, and heal quite slower than my tractor would if it failed. PLUS even with pretty good insurance, the tractor repair might be cheaper! LOL but reality too.

So I am just trying to get a gut feeling for how much I might be risking as far as tractor damage goes should I do what I think makes most sense for me at the expense of possible tractor damage.

I really do appreciate any guidance and advice members here give. I learned long ago that whatever I might think can often use readjustment.

Understand. It’s a legitimate question.

My main concern with a failure would be its most likely to fail when under maximum stress which would put the failure being most likely on the low side when you’re side sloping it near capacity. A failure on the low side while your sideways on a slope could easily put you on your head, particularly if it’s a truly catastrophic failure, rather than just a prematurely worn bearing. Metal fatigue can be a killer if an axle fails.

Cost of the potential failure would be a consideration but it would be a secondary consideration for me. I don’t want to spend the money on repairs or a completely new machine but I could if necessary. I only have one of me so I agree the safety issue would be paramount and if you grossly exceed design specs it could be a serious safety issue, just a less obvious safety issue than you currently have.

I’ve seen (and I suspect you have as well) numerous catastrophic failures of overly modified trucks, cars, farm equipment, and construction equipment. Tweaking performance can be extremely helpful IF you keep it within reason to not set yourself up for causing a failure of systems (in this case the axle and axle housing) where failure simply isn’t an option.

Edit: If you do go with the 6” spacers, hope it works well for you. I don’t know enough to know what the actual failure point would be and I wouldn’t care to find out the hard way, but most of life is a calculated risk so let us know how it works out if you go with the max width spacers.

 

[Mark_BX25D]

Nobody other than a design engineer at Kubota can reliably answer that question.

This is the only correct answer. Anything else is just unqualified guessing.

It's one thing to wear out a bearing prematurely. It's quite another to have an axle break and dump you down the slope.

Leverage and vibration can do amazing things.

 

[GreensvilleJay]

re:
Nobody other than a design engineer at Kubota can reliably answer that question.

This is the only correct answer. Anything else is just unqualified guessing.

Actually he doesn't really know.... the guy TESTING the tractor IS the one who DOES know !

There's a software simulation package for microcomputers ,used around the World, supposed to be the cat's meow...'greatest thing since sliced bread'. I pointed out to a rather talented electrical engineer a simple,basic FLAW in EVERY schematic that was designed... 'works in the simulation', does NOT work in the Real World. I said I'll wager everything I own against his bank account. he declined.