IT was my original statement, and YES I am saying that loaded rears and a 600# implement is NOT enough.
Will it be enough to lift some pretty hefty logs....sure. When I tow my dump trailer to the woods to load logs I dont have the option of also having an implement because I use the tractor to tow the trailer. I load some big logs.....if I cant lift it....I just cut it shorter. My limitation is not the strength of the loader, rather the lack of rear weight.
Loading tires is great, and its step 1....but that doesnt do anything to unload some weight off the much smaller front axle. So if you want to use the front loader to max capacity...you need something on the 3PH.
Now when I say 600# isnt enough....thats only partly true. Because you have a lever effect. Think of it in terms of ft-lb.
By bushhog is 1620 pouns. Its center of weigh is about 5' behind the center of the rear axle. SO in other words...I have 8100ft-lbs of counter weight about the rear axle.
My rear blade is 1250lbs. Its center is a little farther back at about 6' back. So about 7500ft-lbs of counterweight.
SO.....that said, 600# mounted on a boom bole about 12-13 foot back would have the same effect
When it comes to weight BEHIND the axle, TWO things to increase effectiveness. Weigh, and length. Bushhogs are good, they stick way back. Box blades or tillers are less effective. A 800 pound bushhog is WAY better for
ballast than a 800 pound box blade. Now whether they are practical for your uses or whether the length will be a hinderance if you are in tight areas, only YOU can answer.
Regarding tire ballast.....The R1 (ag) tires hold about 45 gallons per tire. Mine are filled with windshield washer fluid. So thats only ~342 lbs per tire....Just shy of 700# for the pair. Rimguard is ~11 pounds per gallon so you could get 1000 pounds with them.
But again.....not nearly as effective as weight farther back. Think of this, your 3PH arms are already about 3' behind the rear axle....some even something short like a ballast box or tiller thats gonna put it another foot back, for a total of 4' behind the rear axle......your 1000 pound tire ballast is essentially only as effective as a light 250lb implement hanging off the back. So keep that in mind when your thinking that 1000lb of ballast is alot