I've a 4010 with 410 loader, 49" bucket. I hauled 19.5 tons of #5 gravel with it recently and figured out how to handle it to fill the bucket to the brim. The rear tires are loaded with windshield washer fluid. I did the work with an old JD M soil ripper (cut to 50" instead of original 60") on the 3 pt and a couple 4x4s and a couple bags of mulch on top the 2x2 bar in addition to the 7 chisel plows. Felt it needed it going down my trail that has a slight slant left down the hill as it crosses the hill. Before I put the mulch bags onto the bar, I had the right rear wheel tilt up on me once as I lifted the bucket slightly to dump it. With the 2 bags on the bar, it was fine. The soil ripper stuff is probably around 200 #. The bags were 40# each, so a total of near 300# in addition to the rear tire loading.
I'd get SOMETHING to put on the 3 pt, a ballast box, old ripper like mine or BH, whatever. If you're lifting mulch or other light stuff, OK, but with gravel you need some added weight back there.
Ralph