I have lifted a lot of hard wood stems over 24" in diameter, Red and White Oak, White Ash, Beech, Maple with no problem along with some pretty big rocks as wells. I have an Artillian fork frame which is real light weight. The frame is 73 lbs and the forks are 48" and my guess is that they are close to 100 lbs each so we are talking under 300# for the fork. The spec on the 300CX with the 4005 which was the same as the 990, they just changed the model # and it had a 40 amp alternator instead of a 20 amp alternator, (mine was a late model 990 so a lot of the parts are the exact same as what are on the 4005) as follows from this site
https://tractorsinfo.net/john-deere-4005/
John Deere 4005 Attachments
Loader type: | John Deere 300CX |
Weight: | 856 lbs [388 kg] |
Height (to pin): | 103.9 inches [263 cm] |
Dump reach: | 21.7 inches [55 cm] |
Dump angle: | 45 |
Rollback angle: | 27 |
Breakout force (at pin): | 3015 lbs [1367 kg] |
Breakout force (at 500mm): | 2158 lbs [978 kg] |
Lift to full height (at pin): | 1256 lbs [569 kg] |
Lift to full height (at 500mm): | 887 lbs [402 kg] |
Lift to 1.5m (at pin): | 1797 lbs [815 kg] |
Lift to 1.5m (at 500mm): | 1395 lbs [632 kg] |
Raise time to height: | 3.57 s |
Bucket dump time: | 3.04 s |
Lowering time: | 2.11 s |
Rollback time: | 1.79 s |
If you look at the earlier models of the 990 they used the older 430 FEL and its specs at lift to full height were about the same but they were better at 1.5 M lift compared to the later models which were sold with the 300CX. I am going to guess there was some better leverage with the 430 due to its design compared to the 300CX. They sloped the 300CX. Of course it could be cylinder size. I have thought at times to replace the cylinders with a little larger ones and that would give me some more lift as well. I do not like the idea of messing with the hydraulic pressure although I have toyed with the idea before since it is not too hard to do.
John Deere 990 Attachments
Loader: | |
Loader type: | John Deere 430 |
Height (to pin): | 101.9 inches [258 cm] |
Clearance, dumped bucket: | 78.3 inches [198 cm] |
Dump reach: | 25.3 inches [64 cm] |
Dump angle: | 45 |
Reach at ground: | 51.2 inches [130 cm] |
Rollback at ground: | 30 |
Rollback, raised: | 64 |
Breakout force (at pin): | 3,285 lbs [1490 kg] |
Breakout force (at 500mm): | 2,306 lbs [1046 kg] |
Lift to full height (at pin): | 1,102 lbs [499 kg] |
Lift to full height (at 500mm): | 915 lbs [415 kg] |
Lift to 1.5m (at pin): | 1,943 lbs [881 kg] |
Lift to 1.5m (at 500mm): | 1,724 lbs [782 kg] |
Bucket width: | 61 inches [154 cm] |
Raise time to height: | 3.9 s |
Bucket dump time: | 1.8 s |
Lowering time: | 3.0 s |
Rollback time: | 2.2 s |
If you look at just the 300CX loader which was also used for the 3x20 series CUT's the capacity was much better as these different site specs
https://www.gardenguides.com/13424296-specifications-for-a-john-deere-300cx-loader.htmlhttp://tractorgearbox.com/jd_300cx_front_end_loader_specs.html
Lifting Capacity
The 300CX will lift 1,122 lbs. to a maximum height of 102 inches, measured at the bucket edge. Measured from the pivot pins, the capacity is 1,598 lbs. The first rating is a more realistic measure of what you can expect from the loader, while the pivot pin rating relates more to gross lifting power. With a height limit of 59 inches, those capacities increase to 1,649 lbs at the bucket edge and 2,125 lbs. at the pivot pins.
and
John Deere 300CX Front End Loader Specs
Compatible Tractor Models
Tractor Model .......... John Deere 970, 990, 3520, 4005, 4300, 4400, 4410
Front tires .......... 25x8.50-14.6 PR R4
Rear tires .......... 15.00-19.6 PR R4
Wheelbase .......... 1727 mm (68 in.)
Hydraulic System Rated flow .......... 32.5 L/min. (8.6 gpm)
Maximum pressure .......... 17.238 MPA (2500 psi)
John Deere 300CX Loader
Loader Model .......... JD 300CX Loader
Leveling System .......... Non-Self Leveling
Bucket
Width .......... 1550 mm (61 in.)
Length .......... 633 mm (25 in.)
Mass .......... 93.8 kg (206.8 lb.)
Cycle Times (Seconds)
Loader raising time .......... 3.56 seconds
Loader lowering time .......... 2.1 seconds
Bucket dumping time/regen .......... 2.96/1.21 seconds
Bucket rollback time .......... 1.75 seconds
Lift Height (Maximum)
To pivot pin .......... 2593 mm (102 in.)
With level bucket .......... 2388 mm (94 in.)
With bucket dumped .......... 2024 mm (79.6 in.)
John Deere 300CX Loader Dimensions
Overall Length .......... 3216 mm (126.6 in.)
Dipping Depth .......... 143 mm (5.6 in.)
Reach
At max. lift height .......... 562 mm (22 in.)
With bucket on ground .......... 1489 mm (58.6 in.)
Angles (Maximum)
Max. dump angle .......... 41.1 degrees
Max. dump angle at ground .......... 128 degrees
Max. rollback angle .......... 31 degrees
Rollback angle at full height .......... 119 degrees
JD 300CX Loader Lift Capacity
To max. height at pivot pin .......... 725 kg (1598 lb.)
To max. height 500 mm forward of pivot point .......... 509 kg (1122 lb.)
To 1.5 m (59 in.) at pivot pin .......... 964 kg (2125 lb.)
To 1.5 m (59 in.) 500 mm forward of pivot point .......... 748 kg (1649 lb.)
Breakout Force
At pivot pin .......... 14800 N (3327 lb-ft.)
At 500 mm forward of pivot point .......... 10750 N (2416 lb-ft.)
Bucket Rollback Force
At max. height .......... 7950 N (1787 lb-ft.)
At 1.5 m (59 in.) lift height .......... 13230 N (2974 lb-ft.)
At ground level line .......... 13730 N (3087 lb-ft.)