A worn swing pinion announces itself as backlash and clunking at the start and stop of every swing. Because the pinion meshes with the swing bearing's ring gear, the two wear together — fitting a new pinion against a damaged ring, or the reverse, shortens the life of both. The documented listings below are the pinion shafts on record, all for Caterpillar E-series machines.
Documented listingsDocumented Gear Part Listings
| Part number | Part | Compatible with | Machine models |
|---|---|---|---|
| 099-0231 / 7I-2111 | Swing pinion shaft | Caterpillar | E120 |
| 114-8225 / 1148225 | Swing pinion shaft | Caterpillar | E312 |
| 148-4636 / 1484636 | Swing pinion shaft | Caterpillar | E318C, E319C, E320C |
| 148-4605 | Swing pinion shaft | Caterpillar | E330C, E330D, E336D |
| 1912694 | Swing pinion shaft | Caterpillar | E325C, E329D, E324D |
Checking the Mesh Before You Order
- Inspect the ring gear teeth through the swing bearing's inspection points; hooked or chipped teeth change the order from a pinion to a pinion-and-bearing job.
- Measure backlash if you can — the figure tells whether wear is pinion-side, ring-side or both.
- Send the pinion's part number and machine model; tooth count and module make visual matching unreliable.
- Photograph the tooth profile of the old pinion if the number is worn away.
Gear and travel components sit alongside the final drive and travel gearbox listings. A gearbox is quoted as a replacement assembly by its documented number, not as a repair item: the assessment route in the hydraulic repair solution covers its named components — hydraulic pumps, travel motors, swing motors and main control valves — and gearboxes are not among them.
Delivery and preparation times are confirmed for your order in the enquiry reply, in writing and before payment: the reply states the times, the packing and the shipping method that apply to your exact part number. Times are confirmed per order rather than published as a general figure, because they follow the listing, the quantity and the destination.
Frequently Asked Questions
Should I replace the pinion and swing bearing together?
Only if both are worn. Inspect the ring gear first: a sound ring with a worn pinion needs the pinion alone, and the inspection evidence — photos and backlash — is what the reply will ask for.
Do you document gear parts for other brands?
The documented extract is Caterpillar-centred. Other gear parts are confirmed by part number against the Gear Parts category — ask with the number rather than the machine name alone.
Do the parts carry a warranty?
Warranty terms are confirmed in writing for each order before payment. Kyotechs' own FAQ states that most parts are backed by a warranty against manufacturing defects; ask for the term that applies to your listing when you enquire.
Pinion Wear: What the Teeth Tell You
A removed pinion is a record of its own failure. Even wear across all teeth is hours — normal service life, replaced on condition. One-sided or hooked wear points to misalignment or a ring gear worn to match, which means the ring must be inspected before the new pinion is fitted or the new teeth will wear into the old pattern within months. Chipping suggests shock loads or debris through the mesh — check the swing bearing's grease for metal and the gearbox oil for fragments. Photographing the tooth faces and sending the pictures with the part number turns the enquiry into an assessment: pinion alone, or pinion with bearing work, quoted on evidence.
Gear lash, finally, is a system measurement: a new pinion fitted against a worn ring gear takes up the old wear pattern, so backlash is checked after fitting and compared with the maker's range rather than assumed. If the measured lash sits outside the range with correct parts, the ring gear itself is the next inspection — better decided on the bench than discovered as a clunk in service.