Where the J400 nose sits in a 980 fleet
The 980 line has been on two different tooth rungs over its production life, and both castings are still in service on the same yard. 6I-9898 is the J400 centre top bolt-on base: 460 mm long, 156 mm wide, 45 mm deep, 1.75 in plate, printed for 980G, 980H, 980F and 980C in the inch catalogue and for 977, 983 and 980 in the metric one. The J350 casting 1U-1357 that sits under it is 430 mm long on the same 156 × 45 mm footprint.
So the two bases differ by 30 mm of length and 8.85 kg of metal, and everything downstream grows with them. That is the price of the larger nose: a bigger tooth, a bigger pin, and a bucket that carries 212.3 kg more wear metal on a 24-point lip before a single tooth is worn out. On a machine that loads abrasive rock, that extra metal is the reason the corners survive a campaign; on a machine that rehandles gravel, it is weight the loader lifts for nothing.
The two weights printed for one casting
This is one of the numbers we refuse to average. The metric catalogue in our files prints 6I-9898 at 27.5 kg. The inch catalogue prints 63.2 lbs, which is 28.67 kg — 1.17 kg more. Neither book is obviously wrong; they were compiled at different times and probably from different samples. The practical consequence is that a quotation written from the metric book understates the shipment by about 28 kg on a 24-point set, and that is the kind of discrepancy that shows up as a freight argument at the destination port.
Our own practice: quote 27.5 kg as the catalogue figure, weigh every casting on the shop scale, and put the weighed figure on the packing list and the bill of lading. Buyers who need the weight for a container load should ask for the weighed figure rather than the printed one. The same applies to 1U-1357, where the books happen to agree at 19.8 kg (43.7 lbs = 19.82 kg), and to 3G-3357, where they do not: 16.9 kg metric against 43.3 lbs (19.64 kg) inch.
The J400 teeth and what they weigh
| Profile | Tooth | Weight | Against the J350 equivalent |
|---|---|---|---|
| Standard short | 7T-3401 | 18.9 lbs / 8.57 kg | 1U-3351 short is 12.8 lbs — 32 percent less |
| Standard long | 7T-3402 | 20.8 lbs / 9.43 kg | 1U-3352 standard long is 12.9 lbs — the J400 tooth is 1.61 times the mass |
| Heavy duty long | 8E-4402 | 25.4 lbs / 11.52 kg | 9N-4352 heavy duty long is 17.6 lbs — the J400 tooth is 1.44 times the mass |
Those ratios are the honest way to describe the upgrade: the J400 system is not a better tooth on the same nose, it is a heavier tooth on a heavier nose. The 7T-3408 pin with retainer 7T-3409 is what holds it, and the catalogue prints a second J400 retainer row for radius groove teeth — so the pair is quoted against the tooth number, never assumed from the rung.
Confirming 6I-9898 against 1U-1357 on a real bucket
The two castings look similar on a bench and the difference is measurable in one place: the length of the base from the back face to the nose.
| Check | 6I-9898 (J400) | 1U-1357 (J350) |
|---|---|---|
| Base length A | 460 mm | 430 mm |
| Base width B | 156 mm | 156 mm |
| Depth C | 45 mm | 45 mm |
| Plate thickness | 1.75 in (44.4 mm) | 1.75 in (44.4 mm) |
| Tooth series printed on it | J400 | J350 |
| Printed weight | 27.5 kg / 63.2 lbs | 19.8 kg / 43.7 lbs |
Because width, depth and plate thickness are identical, a tape across the side of the base will not tell the two apart. Measure the length, or better, read the tooth: a J400 tooth on the nose means the base is 6I-9898; a J350 tooth means it is 1U-1357. The tooth numbers do not cross the rungs, and neither do the pins — J400 teeth run 7T-3408, J350 teeth run 8E-6358 or 9J-2358 depending on the groove.
How to order
- Say J400 and give the machine. 980G, 980H, 980F and 980C are the printed lines; a 980B or a 988 is a different table.
- Quote teeth with the base. The base is useless without 7T-3402 or 8E-4402 on it, and the tooth is where the wear life is decided.
- Take the pin and retainer on the same line. 7T-3408 / 7T-3409 for the standard row; state the tooth number so the correct retainer row is picked.
- Add the corner castings separately. Corners are their own numbers on this nose — a 24-point lip is not 24 centres.
- Ask for the weighed figure if you are booking a container. The two catalogues are 1.17 kg apart per casting on this number.
FAQ
Q: Which loaders take the Cat 6I-9898 adapter?
A: 980G, 980H, 980F and 980C per the inch catalogue; 977, 983 and 980 per the metric one. It is the centre top bolt-on base in the J400 group — the rung above 1U-1357, which the same 980-class machines also run.
Q: Is 6I-9898 a J350 or a J400 base?
A: J400. It takes 7T-3401 (18.9 lbs), 7T-3402 (20.8 lbs) and 8E-4402 (25.4 lbs) on pin 7T-3408 with retainer 7T-3409. A J350 tooth will not seat on it: the nose is 30 mm longer than the J350 casting 1U-1357.
Q: How much heavier is the J400 nose than the J350 nose?
A: 63.2 lbs (28.67 kg) against 43.7 lbs (19.82 kg) — 8.85 kg per point, 212.3 kg on a 24-point lip. The tooth grows too: the 7T-3402 is 20.8 lbs against 12.9 lbs for the J350 1U-3352, 1.61 times the mass.
Q: What bolts hold it?
A: Bolt 5P-8361 with nut 5P-8362, 1.25 in (31.8 mm) — the same hardware printed against 3G-3357 and 1U-1357, so a mixed J350 and J400 order shares one fastener line.
Sources
Adapter numbers, published weights, printed A × B × C dimensions, plate thicknesses, machine lines and bolt and nut pairs on this page are taken from the loader adapter tables of the Black Cat Wear Parts replacement catalogue (inch, lbs) and the COHIDREX TRASTEEL TSJ catalogue (metric, kg / mm) in our files. J400 tooth weights and the 7T-3408 / 7T-3409 pin and retainer pair come from the J-series teeth and pins table of the same inch catalogue, read by column position on the page. Caterpillar and the part numbers referenced are the property of their respective owners and are used here for fitment reference only. Differences between the two catalogues are shown, not averaged.