Swapping Wheels for a Wider Track

[Bluest]

I'm going to switch the rear wheels, left to right to give me little wider track for slope work (every little helps!). Question is, do I swith the fronts too? Instinct says yes, but thought I'd check.

 

[CobyRupert]

Oh boy, you've might be opening a can of worms with this question.
Does it help? The answer is sort of like my facebook relationship status: "It's complicated"
That is, given that the front axle pivots, a wider front stance has a limited effect, but I widened mine when I widened the back tires.

 

[Bluest]

I thought as much! I suppose what I should have asked is; would switching the front wheels around have any negatives? It isn't going to throw the steering ackerman out by miles or anything like that is it?

 

[winston1]

I wouldn't even consider it with my 4 wheel drive with a loader. Having said that, the strain on your front might not be to bad without a loader. And having said that, I don't think it is going to help your stabilization that much. Just and opinion, no facts.

 

[joe swanson]

I HAVE A 336d AND THE REAR WHEELS AR MADE TO BE MOVED INAND OUT. I CAN GO FROM ABOUT 48" TRACK T 60". DEFINATELY HELPS STABILITY . AS TO THE FRONT TIRES DON'T EVENTHINK IT IF YOU HAV A FRONT END LOADER.

 

[Bluest]

What's the concern with the fronts then? Is it that the extra width will increase the wheels leverage on the stub axle or bearing?

 

[California]

Look at this this way - the front wheels have the correct offset, dish, to center the weight over the inner and outer wheel bearings. Reverse the front wheels to increase track width and you have a much greater load on the outer wheel bearing than what it was designed for. Even the 2wd Yanmars occasionally break a spindle. I assume the 4wd's could too. You don't want that spindle to snap on the downhill side of a slope, or while driving with an unbalanced load in the loader bucket raised up a little too high. Don't do it.

And an unrelated consideration re geometry: Since there are no front springs, there is no resistance to rollover until the chassis comes down to meet the front axle. I think by that time you are tilted so steep you have a rear wheel far off the ground, meaning you no longer have engine compression to slow you down - so you are out of control rolling forward as well as tipping over, and will be lucky if it doesn't kill you. Widening the front track won't reduce how far the tractor tips. The only solution to this risk is to operate cautiously so you never get in such a desperate situation.

 

[normde2001]

Due to the pivoting front axle the front end has no bearing on stability until/unless the pivot bottoms out, then it is going over anyway. The load extending out past the ends of the lightweight spindles has caused lots of broken spindles and prematurly worn bearings.

 

[California]

Dang I'm too wordy. :ashamed:

Norm said it better. :thumbsup:

 

[CobyRupert]

Here we go.
IMO, unless you actually widen the front axle, like you can on some 2WD tractors, you're not changing the span or therefore the stress on the bearings. That is, IMO, if there's torque on the bearings because of the rim' s offset, there's still the same torque when you flip the rim just in the opposite direction.
I'm sure many disagree.

 

[California]

Huh? if the downward load is out beyond the outer wheel bearing then that outer bearing is carrying 100% of the weight - in contrast to an original design that shares the weight equally on inner and outer bearings.

 

[deepNdirt]

I'm not at all familiar with the f-14d , so I was curious to find out, a google search provided images of several pages, each showing the wheels in the correct position, It appears that no one else cares to flip the front wheels,
Just saying!
Though I've not giving much thought as to why the wheels have such a shallow offset, I always thought it had to do with providing room for front wheel weights, I'm sure it has much more to do with it...

 

[Bluest]

I think I'll leave them as normal. Based on he above, it sounds like, with the wheels the correct way round, the centre of pressure is carried equally by inner and outer wheel bearing. Flipping the wheels will move the centre of pressure outwards, possibly overloading the outer bearing, or putting too much strain in the stub axle.

 

[normde2001]

Exactly, + it has no benefit.

 

[Kernopelli]

As far as reversing the front rims, I can't speak for Yanmar but I did it on my current Mitsubishi years ago. I have run close to 1000hrs (with loader) with this set up. I first did it because the front wheel track was not wide enough to straddle my front ditch. The front rim reversal made mowing it much easier......in fact it made a difference that allowed me to be able to mow it when I previously couldn't w/o often getting stuck or making a real mess. The old Iseki TX models were actually designed to run the front rim dish in either direction and the owner's manual gave the outline for the process and their wheel track dimensions when dished in or out. Many various make/model owners say their owner's manual say in no uncertain terms not to reverse the front rims.

I have had no ill effect other than increased steering and bump steer effect.....that said, my Mitsubishi and the old TX1300/1500's were obviously designed to handle the increased stresses of reversing the front rims and some make/models aren't. TBN member Ilikeurtractor actually posted a very good PDF engineering analysis based on actual data for a TX1300. When rims were dished out, it made an outer bearing stress increase of 63% and inner bearing increase of around 157%. While every machine is going to produce a different bearing load value, I suspect these numbers could be used as a good general reference.

 

[GWKID]

Due to the pivoting front axle the front end has no bearing on stability until/unless the pivot bottoms out, then it is going over anyway. The load extending out past the ends of the lightweight spindles has caused lots of broken spindles and prematurly worn bearings.

Not to mention the problem of steering with a full loader and no power steering. I wouldn't do it.