So do you think the front axle (aka fulcrum) may not be designed to support all of the weight. I suspect when you lift 1500 pounds in the bucket of a tractor that weighs 3000 pounds and the rear wheels come off the ground you are essentially putting 4500 pounds on the front axle. I have trouble seeing where adding 1000 pounds to the rear end to hold it down takes any load off the front axle but rather just keeps the rear wheels on the ground.
Partially correct. Its like an arc, or rainbow. With the left being NO added ballast of any kind. And the far right being an infinite amount.
Lets use my
L3400 weights for example. Empty non-ballasted weight of bare tractor + loader is ~3750#. With NO ballast, the FEL may only be able to lift ~250# before the rear raises. Placing a total load of 4000# on the front.
Add a 500# disk to the rear, and now the loader might be able to lift 750# but the rear still raises. So 3750 + 500 + 750 = 5000lbs now on the front.
Add 1000lbs ballast, and now loader might be able to lift 1000lbs, BUT, the rears stay planted, AND because the 1000lb ballast hangs off the back, relieves some of the weight from the front, and say keeps 1000lbs on the rear axle. So, 1000lb ballast+ 1000lb load + 3750lbs tractor = 5750lbs, but 1000lbs stays on rear. Now we are down to 4750lbs on the front.
The more ballast added to the rear from this point will only reduce weight on the front, since loader is maxed out.
If to an infinite amount of rear ballast that makes the rear axle become the pivot, and the front axle sees NO load. And even with a max load in the bucket, the front axle stays in the air.
So adding ballast BEHIND the axle does indeed increase front axle load, up to a point, and then it starts coming back down. That is why "sufficient" ballast is needed. And ofcourse this is only when dealing with max loads too. Smaller loads can get by with lesser ballast and still be taking weight off the front axle.