2wd Always?

[patrick_g]

I used to shift in and out of 4x4 more with my Kubota 4610 with HST but last few years just leave it in 4x4 unless I am driving on pavement or even driving fast where I know 4x4 is not needed such as on a gravel road if I am going very far. Otherwise I just leave it in 4x4.

If anyone could make a good argument for needing to "manage" it more and swap it back and forth, I'd be happy to reconsider my actions. I don't care about a couple inches of turn radius or a little more surface disturbance.

Pat

 

[N80]

We can leave out the measurement variable too. Try this: [Go around the circle at your steady slow speed in 4wd. Then without stopping flip the lever to 2wd while watching the front wheels carefully.] It is likely, almost assured, that there will be some resistance to operating the lever, and that when 4wd disengages the front of the tractor will slew somewhat toward the center of the circle.

I'll give it a try next weekend.

Whether a difference is insignificant will be relative to the use. An advantage in maneuverability, however slight, becomes less and less insignificant as constrained repetition of movement is required.

Very true.

You mentioned that we are wasting time with this. I view it as an opportunity to learn. Your tractor is exhibiting operation in a manner different than any I have encountered. Learning why has value to me.
larry

The waste of time usually comes from the repitition of things already said. But, on this site, rarely does any thread fail to teach me something new.

My tractor surprises me too. I've driven 4wd things all my life from Willys jeeps, early Scouts, AM General trucks to modern 4wds and a few modern 4wd tractors. I can say without hesitation or exaggeration that I cannot sense in any way when my tractor is in 4wd in terms of steering or feedback through the steering wheel or resstance to turning. Obviously I can tell in terms of traction and I have also inadvertantly left it in 4wd on pavement. Even then, there is no feel of binding or scuffing. But the front end whines and I notice that pretty quickly and take it out. That's my biggest argument against leaving it in 4wd......but then again, I only hit pavement maybe 4-5 times a year and then just a short distance.

 

[Egon]

Spyderlk:

Nope, not even close to the trailer maximum. It's just the way way I like to keep it.

And yeah, I may not be too wise but I do know what I'm doing! Sometimes!

 

[Mighty Dodge]

I only use 4wd when necessary. The county road boarders two sides of my property so to cut down on wear and tear on the lawn I use the road a lot. You could leave it in 4wd all the time but you'll wear out your tires faster if you run on pavement in 4wd.


M.D.

 

[EddieWalker]

When I bought my tractor, I kept it in 2wd as often as possible. My thought was that I'd save fuel and there would be less wear and tear on the front driveline. Every time that I used it, I would need to put it into 4wd for one reason or another.

Then it hit me, this is a tractor, not a Jeep. I was thinking of my tractor in the same terms that I applied to my vehicles. This is/was a mistake on my part. The fuel savings is so insignificant as to be impossible to measure. Did I burn a percentage more of fuel in 4wd then 2wd? Probably, but with a ten gallon tank and running it all weekend, I don't know how to measure the difference.

I run my tractor on dirt all the time. I'm sure there is some small amout of wear that comes from leaving it in 4wd all the time, but again, it's not like I'm driving it 10,000 miles a year like I would in one of my vehicles. I doubt I'll put 1,000 miles on it in ten years!!!!! The wear issues just isn't enough to be measurable.

There is the getting stuck consideration. If you get stuck in 2wd, then hopefully you can get unstuck in 4wd. This never worked for me on the tractor. If I got stuck in 2wd and locking in the rear diferential didn't get me out, then 4wd didn't either. For me, when I get stuck, it's because I've sunken into a pit of mud and there's no hope of getting out without the backhoe to pull me out. It's always when mowing and the weight of the mower is the biggest issue. Without the mower on the back, I can drive through just about any puddle or mudhole and not get stuck. The R1 tires are awesome. In fact, if somebody in a car/truck/van gets stuck at my place, the first choice to pull them out is the CUT. I have three tractors, but that small 35hp 4wd tractor is the easiest and most reliable at pulling them to solid ground.

My full sized backhoe is 2wd and pretty much useless in my mud. There is no comparison between them in traction and their ability to get around in wet conditions.

I don't see any difference in turning radius from 2wd compared to 4wd. I guess if I spent allot of time doing really tight U turns, I might consider this imporant, but it's not an issue either way. Sharp turns mean I'm tearing up the ground, so I try to avoid them anyway.

I keep my tractor in 4wd all the time now. For me, and as far as I can tell, there is no measurable advantage to 2wd over 4wd, yet there are all sorts of advantages of 4wd over 2wd. Mostly traction and the ability to keep on moving instead of hitting a spot that I can't move, spin my tires or bog down the engine. When I'm on the tractor, I want to keep working, not fiddle around with anything more then I have to. Changing from 2wd to 4wd and back again is just not something that I'm going to deal with anymore.

Eddie

 

[patrick_g]

About the turn radius thing...

If you are puling something heavy or say dragging a box blade with it full and scarifiers digging in then your turn radius is increased and the front tires have to provide more steering force to turn you. If you are on a hill side that is slippery the front wheels when in 2x4 don't PULL the front of the tractor in the direction they are pointed. In these situations 4x4 will turn quicker.

I think the turning radius of a tractor being driven in circles with no working load to compare 4x4 to 2x4 is perhaps interesting as a discussion topic but not too useful to me as it doesn't relate to the situation when doing real work. If I am working the tractor and not practicing square dancing with it then most of the time it turns shorter with 4x4 as the driven front pulls the front of the tractor around instead of plowing along some.

I do not claim that you can't find some particular situation where 2x4 will turn sharper. I claim that is not the case for me in most working situations.

Pat

 

[N80]

I think the turning radius of a tractor being driven in circles with no working load to compare 4x4 to 2x4 is perhaps interesting as a discussion topic but not too useful to me as it doesn't relate to the situation when doing real work.Pat

Well, you have to have a point of reference. A baseline. Without that you get everyone claiming disparate experiences based on varying loads, configurations, soil types, tire types, etc etc and that usually provides no useful info for anyone either. My point is that the baseline for a tractor like mine is that there is no significant change in turning radius between 2 and 4wd and therefore that need not be a major consideration when it comes to deciding when to use 4wd or not. In other words, on my machine there is no 'penalty' to leaving it in 4wd in regard to maneuverability. And based on your experience there are situations where it can be a benefit and I concur with that. And that sort of sums it up for me. Plenty of practical, day-to-day benefit of leaving it in 4wd vs a few theoretical benefits to leaving it in 2wd.

Have we made 4 pages yet?

 

[RobJ]

Well, you might not believe the earth is round either, but that doesn't make it flat! My tractor has a bevel gear front drive system. There is no difference in feel or turning radius between 2 and 4wd. Sorry if that seems inconceivable, but welcome to the 20th century....Kubota has been making them this way for years.

What's a turning radius? I think any L or bigger has a separate brake so I have a ZTR...so to speak.

And isn't this the 21st century?

BTW, you should operate your 4wd lever from time to time to make sure it works and all. Call it PM.

 

[RobJ]

Yes, it must be some difference in models. Theres some sort of magic going on. The problem that arises with 4wd turning is that the tighter the radius being turned the more discrepancy exists between the summed distances moved by the fronts and the rears. The tighter the turn the further the fronts go compared to the rears. Fronts that are well overdriven are great for turning, but fronts that are driven just right to work neutrally along with the rears when going straight are not. In turning these fronts are being pushed by the rears, but being forced to run at the same tread speed as the rears by the linked system. They slide causing a wider circle. Normally, fronts are overdriven slightly, gently sratching along trying to stretch the tractor. More would be better for maneuverability, but with a loaded loader and counterweighted tractor the forces on the drivline would be abusive when going straight. It becomes a balancing act. I dont see any way this system dichotomy can be fully resolved in a system hard linked front to back.
larry

This is funny... oh your serious....my bad.

 

[RobJ]

I have been told, or I read it in the shop manual, that the fronts on the L4400 are slightly overdriven.

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!! )