Four wheel drive

[BB_TX]

I think it comes down to the fact that on true four wheel drive, the front drive components are built as strong as the rear drive components and designed to carry an equal load. On front wheel assist, they are not designed as heavy as the rear, and are there to carry only a fraction of what the rears are designed to carry.

 

[Farmwithjunk]

Call it 4WD, Call it Charlie, Call it whatever you like. If it does the job, and you're happy, just call it a good thing! /forums/images/graemlins/grin.gif

I'm not much on titles or names or symbols, or, well you get the idea. /forums/images/graemlins/wink.gif /forums/images/graemlins/smirk.gif

My dad always told me that 90% of his employees were happier with a title than they were with a raise. /forums/images/graemlins/crazy.gif

 

[EFR2441]

Gentlemen: Thank you for all your help. What the dealer told me got me nervous. Mr. Steve, the front drive shaft on the NH was exposed, and was noticably smaller than competitors models. What you folks told me makes sense. I was worried that the NH models were not a true 4wd (or whatever they want to call it) as opposed to the JD, Kubota, or others. For obvious reasons, having power to the front wheels is very important to me and my purchasing decision. With this small issue resolved, I'm back to trying to decide which brand and model will be best for my needs (with the NH still in the running). Thanks again for everybody's help and input. Erik

 

[ns_in_tex]

Not sure about other models, but my Kubota L4610 drives all 4 wheels, but you can only lock 3 wheels up tight. Most of the time it doesn't make any difference, but once in a great while, I wish I could lock all 4 wheels.

There is no differential lock on the front axle. This means you can lose traction on one of the front wheels along with both of the rear wheels, under the right conditions. So you are sitting there spinning 3 wheels and wishing the one non spinning wheel had more pull.

Also I think this means you only have as much traction on the front as the wheel with the least traction.

 

[RedRocker]

Most all Jeeps, especially the older models are sold with open differentials. I've been stuck before with two wheels on the ground. Not anymore though, Detroit lockers took care of that little task. Seems like most tractors have a manual locking rear diff, and an open front, not too bad since steering can become a little tricky with a locked up front diff.

 

[RedDog]

<font color="blue">Also I think this means you only have as much traction on the front as the wheel with the least traction. </font>

You said it Neal, and you are correct.

All tractors should be available with a front locker. At least that's my opinion. /forums/images/graemlins/grin.gif

 

[LarryD]

I had a friend (Navy transferred him) who love to rock crawl over in the Columbia River Basin. Seems to me he made a true 4wd using a welder. Of course he needed a trailer as well.

 

[RalphVa]

I think it's virtually impossible to match the wheel circumference travel distance of the front wheels with the rear wheels when they're different sizes. That's the main reason why most will tell you to take them out of 4wd when on hard pavement, to avoid undue front tire wear because the fronts are going a different circumferential distance from the rears.

On my JD, and I'll bet it's true on many of the smaller wheeled tractors, the recommended front tire size is not what came on the tractor. It's what they could probably find in the right quantity/price.

On my Gravely, the original tires were quite a bit larger in width and probably a little bit different in circumference from the replacement tires of the same size. They're different from manufacturer to manufacturer, apparently.

When my JD is in 2 wd, the front wheels will skid sideways some when turning. In 4wd, they don't. Makes a big different in slick or uneven terrain.

There are some Goldini orchard tractors made by JD in Italy that are same size front/rear and not articulated.

Ralph

 

[Youare]

I must admit that 4WD does assist in steering when making tight turns on soft ground. Many times with no weight in the loader bucket and some weight on the 3PH when turning on soft ground the front tires will try to go straight and plow a furrow as the tractor driven by the rear tires tries to go straight.

Once 4WD is engauged and the front wheels are driven they do assist in turning the tractor. They also assist the rear wheels in moving the tractor forward especially if there is any amount of weight in the FEL.

I know with my Kubota the front tires are going at a slightly faster pace than the rear tires when in 4WD.

Randy

 

[MikePA]

<font color="blue"> I think it's virtually impossible to match the wheel circumference travel distance of the front wheels with the rear wheels when they're different sizes </font>
I thought this was usually addressed by having a different gear ratio in the front differential?