2wd Always?
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SPYDERLK
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The bevel drive is great because the steering angle has absolutely no effect on its action. U joint systems have escalating problems at high angles. The main issue with them at high angle is some variance in speed as they turn. Their strength is their superior strength at lower turn angle. Yet it really isnt all that difficult to make the bevels plenty strong. Torque thru the u joints can be reduced with planetary gearing at the wheels. This lets the joint spin faster. That reduces torque they have to transmit and makes the cyclic speed variance during turns happen faster and have less magnitude at the wheel so it averages out better. Still, the bevel set up is superior assuming strength is up to the job. Wish my Mahindra had em!
larry
larry
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RobJ
Elite Member
SPYDERLK said:
I don't know but I wonder if the larger systems have a or considered a CV joint. This would eliminate some of the turning effects of the U joint. If you don't need tight turning a U joint is probably stronger and less maintenance. No boot to tear up, easy to replace, and it's a standard part.
daTeacha
Veteran Member
Awww, Pat, you and I both know there is no such thing as centrifugal force. I won't get into the explanation of what really goes on, though.
The deviation from being a perfect sphere that results from bulging at the equator (hmmm, middle aged earth spread?) is more pronounced in the northern hemisphere than the southern by about 50 feet, if I remember correctly. It may have something to do with the greater density of the crust and continents in the north vs the south.
Or maybe it's because there are so many tractors in the northern hemisphere that they either weigh things down or are all pulling in the same direction and distort the planet.
The deviation from being a perfect sphere that results from bulging at the equator (hmmm, middle aged earth spread?) is more pronounced in the northern hemisphere than the southern by about 50 feet, if I remember correctly. It may have something to do with the greater density of the crust and continents in the north vs the south.
Or maybe it's because there are so many tractors in the northern hemisphere that they either weigh things down or are all pulling in the same direction and distort the planet.
patrick_g
Elite Member
Yeah, Rich, Probably so.
How about centripetal acceleration?
With care I can handle over 1000 lb round bales with my 39 PTO HP Kubota with HST. Don't lift high on a slope or when moving fast or maneuvering. It has no problem lifting 1300 lbs If there is some 3PH weight to keep the back wheels on the ground. In winter (not likely to be much haying taking place) with wet, snowy, or icy ground I have to be more careful and without 4wd I might not be able to access my pastures to deliver bales to the stock.
There is a temptation to lift the bale to see where you are going but it is safer to slow or stop, lift it, look, memorize, lower and proceed and or drive in an "S" shaped manner "clearing turns" to fellow pilots.
I simply could not get my work done with 2wd with this small and light weight of a tractor. I have tried working the box blade in 2wd. Totally bogus. Likewise most ground engaging work.
Of course it is obvious that 4wd does not increase PTO HP, as in actuality it has to take just a little HP away from the PTO to overcome the gear losses in the front drive mechanism. I don't use my tractor as a stationery engine like the threshers belt driven by steam powered tractors. If I can't get to where the work is providently and effectively I can't use my tractor to much advantage. The overwhelming majority of my personal observations indicate the need for 4wd for most of my tasks, even if it is just getting there sometimes.
Except for a few "I wonder what would happen" episodes, I never try to see how much useful work I could get done if I only used 2WD or just used 4WD the least possible like it was exceptionally expensive or something. It would be like limiting my RPM to a really low value to save diesel fuel and engine wear when the lower RPM wouldn't git 'er done. You can't make an omelet without breaking the egg.
No doubt there are experienced operators that when paired with larger more powerful and HEAVIER tractors with 2wd could do much of what I do, but I seriously doubt they could do it all as well and as efficiently as I do with the smaller tractor and when it comes to close in maneuvering around fences, pens, and jobs where you need to tread lightly forget the big powerful heavy tractor trying to compete. A tractor a foot or two taller would require many tons of limbs to be trimmed on my trees to let a taller tractor get under them.
After over 6 years with this tractor doing most everything I need done on 160 acres, I just can't fathom having a 2WD only tractor for my needs.
No doubt there are plenty of situations well served by 2wd, just not mine.
Excuse me if I am exhibiting an unrealistically limited imagination.
Pat
How about centripetal acceleration?
With care I can handle over 1000 lb round bales with my 39 PTO HP Kubota with HST. Don't lift high on a slope or when moving fast or maneuvering. It has no problem lifting 1300 lbs If there is some 3PH weight to keep the back wheels on the ground. In winter (not likely to be much haying taking place) with wet, snowy, or icy ground I have to be more careful and without 4wd I might not be able to access my pastures to deliver bales to the stock.
There is a temptation to lift the bale to see where you are going but it is safer to slow or stop, lift it, look, memorize, lower and proceed and or drive in an "S" shaped manner "clearing turns" to fellow pilots.
I simply could not get my work done with 2wd with this small and light weight of a tractor. I have tried working the box blade in 2wd. Totally bogus. Likewise most ground engaging work.
Of course it is obvious that 4wd does not increase PTO HP, as in actuality it has to take just a little HP away from the PTO to overcome the gear losses in the front drive mechanism. I don't use my tractor as a stationery engine like the threshers belt driven by steam powered tractors. If I can't get to where the work is providently and effectively I can't use my tractor to much advantage. The overwhelming majority of my personal observations indicate the need for 4wd for most of my tasks, even if it is just getting there sometimes.
Except for a few "I wonder what would happen" episodes, I never try to see how much useful work I could get done if I only used 2WD or just used 4WD the least possible like it was exceptionally expensive or something. It would be like limiting my RPM to a really low value to save diesel fuel and engine wear when the lower RPM wouldn't git 'er done. You can't make an omelet without breaking the egg.
No doubt there are experienced operators that when paired with larger more powerful and HEAVIER tractors with 2wd could do much of what I do, but I seriously doubt they could do it all as well and as efficiently as I do with the smaller tractor and when it comes to close in maneuvering around fences, pens, and jobs where you need to tread lightly forget the big powerful heavy tractor trying to compete. A tractor a foot or two taller would require many tons of limbs to be trimmed on my trees to let a taller tractor get under them.
After over 6 years with this tractor doing most everything I need done on 160 acres, I just can't fathom having a 2WD only tractor for my needs.
No doubt there are plenty of situations well served by 2wd, just not mine.
Excuse me if I am exhibiting an unrealistically limited imagination.
Pat
kbuegel
Member
We leave it in 4wd always. I occasionally put it in 2wd if I'm on paved road or going over lawns that I want to leave as few tracks as possible. But 2wd is for rare occasions, and 4wd is normal operation.
I once left it in 2wd and my wife got stuck in some light mud. She did not know it could switch between 2wd and 4wd. So now I make sure its always in 4wd when I leave it.
I once left it in 2wd and my wife got stuck in some light mud. She did not know it could switch between 2wd and 4wd. So now I make sure its always in 4wd when I leave it.
SPYDERLK
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I had to rebuild the ones on the L2550. It wasnt hard. The power transmission mechanism was fine. The cages in the ball Bs supporting the axle had failed. Must have been an issue preceding my purchase and then developing to failure. Its been worked harder since w/o problem. Maybe there was a bearing upgrade altho the replacements appeared the same.N80 said:
larry
RobJ said:I think you heard it from Spyderlnk.
But I will repectfully ask that you prove it by showing me in the manual. Then I will gladly have some blackened crow with some honey mustard for lunch and dinner.
If you think about the design, lets have the smaller front drive parts try and pull around the rest of the tractor(think Tweety bird pulling Fog horn Leg Horn around all the time). And an overdriven ratio would be all the time. Talk about some excessive wear on the drivetrain and tires.
If this is the case, then I would not recommend leaving it in 4wd all the time. Otherwise, whatever, I have a 2wd tractor.
But for the record I do leave my ATV's in 2wd most of the time, on the Rancher I even installed a Warn 424 to allow this. Much easier to steer but of course my ATV's do not have power steering.
Rob (stomach growling!!
You were talking about rolling ratio of front tires vs back tires when in 4wd.
Here is a good link on the topic.
http://www.tractorbynet.com/forums/...-lag-grand-l-series.html?highlight=tire+ratio
Let me know how you fixed the crow....
jb
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daTeacha
Veteran Member
On my 4/12 pitch ground, 4wd is the order of the day.
Aside from the occasional large rock or log, the biggest things I normally carry around are large square bales, about 1000 lb each. I use the tractor to unload these from the pickup by rigging some ratchet straps around the bale and over a pair of forks on the FEL frame. Then I lift the bale, back it out of the truck, lower it, and carry it up the hill through the gate and into the barn. The trip through the gate and into the barn is on a sidehill in the barnyard, which is sometimes gooey, sometimes frozen, and sometimes just nice.
The bale is oriented lengthwise
Aside from the occasional large rock or log, the biggest things I normally carry around are large square bales, about 1000 lb each. I use the tractor to unload these from the pickup by rigging some ratchet straps around the bale and over a pair of forks on the FEL frame. Then I lift the bale, back it out of the truck, lower it, and carry it up the hill through the gate and into the barn. The trip through the gate and into the barn is on a sidehill in the barnyard, which is sometimes gooey, sometimes frozen, and sometimes just nice.
The bale is oriented lengthwise
crashz
Elite Member
I can't believe its 12 pages in 6 days!
Well, I couldn't read all the posts, but I'll pitch my royal 2 cents in as well. There has been talk of weak front axle components on the JD 790 and since my machine is similar I have been carefull only to use 4x4 whe in slippery conditions. Its not really wear that I'm concerned with, its breakage.
For FEL work I never use it. My reasoning is that if I can't fill the bucket, then I don't have enough ballast. I also let the rear wheels spin slightly rather than slipping the clutch. I'd rather wear the tires (original turfs with great tread and bad dry rot) as they need to be replaced anyway. So the rule on my machine has been to use 2 wheel drive exclusively unless the conditions are so bad that you anticipate being stuck.
Another reason to run in 2 wheel is when using the brakes to turn with a bucket full of dirt. I can turn almost as tight as a skidsteer, which was really handy when working in the close quarters of my fathers building and outside between his equipment.
Well, I couldn't read all the posts, but I'll pitch my royal 2 cents in as well. There has been talk of weak front axle components on the JD 790 and since my machine is similar I have been carefull only to use 4x4 whe in slippery conditions. Its not really wear that I'm concerned with, its breakage.
For FEL work I never use it. My reasoning is that if I can't fill the bucket, then I don't have enough ballast. I also let the rear wheels spin slightly rather than slipping the clutch. I'd rather wear the tires (original turfs with great tread and bad dry rot) as they need to be replaced anyway. So the rule on my machine has been to use 2 wheel drive exclusively unless the conditions are so bad that you anticipate being stuck.
Another reason to run in 2 wheel is when using the brakes to turn with a bucket full of dirt. I can turn almost as tight as a skidsteer, which was really handy when working in the close quarters of my fathers building and outside between his equipment.
RobJ
Elite Member
john_bud said:
You'll have to zoom me in a little closer JB. 2 pages of guys trying to fiddle with the tire size to get or fix a lead/lag problem with R4's. I just skimmed it for the moment.
Crow tastes link chicken you know.
N80
Super Member
RobJ said:Crow tastes link chicken you know.
Yard bird maybe. Here is a link that was given in that thread which seems to suggest, if not prove that front wheel lead is more than an urban legend.
Can I use a different size tire on my 4wd tractor
I was willing to put my tractor on jack stands and measure the number or revolutions in the rear vs front. But now it looks like I won't need to. Besides, if I did someone would point out that with the tires off the ground I would be getting an accurate calculation because that wouldn't give me the true 'rolling circumference' of the tire. Of course I'd just point out that both the front and backs would be unloaded and its the ratio that's important. Phew, glad I don't have to go through all that!
Enjoy your funny black chicken!
Eating crow - Wikipedia, the free encyclopedia
RobJ
Elite Member
N80 said:Yard bird maybe. Here is a link that was given in that thread which seems to suggest, if not prove that front wheel lead is more than an urban legend.
Can I use a different size tire on my 4wd tractor
I was willing to put my tractor on jack stands and measure the number or revolutions in the rear vs front. But now it looks like I won't need to. Besides, if I did someone would point out that with the tires off the ground I would be getting an accurate calculation because that wouldn't give me the true 'rolling circumference' of the tire. Of course I'd just point out that both the front and backs would be unloaded and its the ratio that's important. Phew, glad I don't have to go through all that!
Enjoy your funny black chicken!
Eating crow - Wikipedia, the free encyclopedia
I'll read it later, got to head home across state now. Hey if I gott eat then I gotta eat. But if it's true, then I would only use 4x4 when needed, to me it's placing more stress on the system than a lag.
JMHO...Rob
SPYDERLK
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Yould have to read posts 29,41,61 in this thread to see why the info in that thread is appropriate. And to get the info in that thread, of course, you have to read it.RobJ said:You'll have to zoom me in a little closer JB. 2 pages of guys trying to fiddle with the tire size to get or fix a lead/lag problem with R4's. I just skimmed it for the moment.
Crow tastes link chicken you know.
larry
I moved 20 yards of field dirt Sunday with my little GC2310. The pile had been sitting there for 2 years. I moved it easily with my FEL in 2wd. (Never used the Diff lock either). And I have turf tires on my tractor. (in mud, my fronts just load up in 4wd anyway).
The only time I need the 4wd is plowing deep snow.
I have seen many guys post; they could not go a day without 4wd, and the diff lock.
Apparently each persons property, tractor, and style is different.
The only time I need the 4wd is plowing deep snow.
I have seen many guys post; they could not go a day without 4wd, and the diff lock.
Apparently each persons property, tractor, and style is different.
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