Yeah, Terry, you raise some interesting issues that have trckled through my mind since I bought my tractor.
I've had my L2500DT about 2 years now, and it's been all learning curve for me. Seems like I discover the limits of my machine by challenging it to the point where it just can't respond. Sure, I've read the specs and know that my loader can only lift 883 pounds, but I don't carry a scale around with me, so I generally just go for it and see what happens. When I exceed the capacity of the loader, it simply does nothing. I'll wager I'm not the only guy to do it that way, too.
As for the lower lip of the bucket, I'm amazed that mine is still straight. I've been toodling along, skimming the ground of debris, when one of those stupid, sneaky, low-life, nasty rocks pokes up out of the ground a few inches and jars my tractor to a complete halt. You'd think that would dent, bend or otherwise mutilate the bucket, but nope. Other than removing some paint, it's as if nothing happened.
The worst thing I do to the bucket, stress-wise, is to get the tips of my bucket forks stuck under a root or something while I'm trying an all-out curl or lift. With the added leverage it seems like the bucket lip wouldn't have a chance, but darned if it doesn't match up just fine when I lay a straight edge across it.
Now, I notice that my loader, the LB400, is the same one that's used on the L3000, which has another 5 hp to throw into the hydraulics. Since the limits seem to be set by the loader specs, regardless of what tractor it's on, I assume the real limiting is done by the pressure relief valves on the loader itself. Makes me wonder, though, if having a bigger, heavier tractor (not much, in the case of the 3000) behind the same loader would make things like the bucket more susceptible to damage. Just how well are loaders and buckets matched to the tractors they're attached to?
I'll be listening to what other folks have to say on this thread.