The Kubota KX040-4 runs a 350x54.5Kx86 rubber track — 350 mm (14") wide, 54.5 mm pitch, 86 links, K-series guide lug profile. That K matters more than any other character in the size: order a 350x54.5x86 with the wrong lug profile and it won't seat on your rollers. Here's the full picture — verification, cost, and the undercarriage parts that wear out alongside the rubber.
Kubota KX040-4 Track Size
| Track size | 350x54.5Kx86 |
| Width | 350 mm (14") |
| Pitch | 54.5 mm |
| Links | 86 |
| Lug profile | K (Kubota-specific) |
| Tread pattern | Directional |
| Track weight | ~456 lb each |
Verify on the machine: the size is molded into the rubber on the inside or outside face of your current track. If it reads 350x54.5x86 or 350x54.5Kx86, this is your track.
Shop Kubota KX040-4 rubber tracks (350x54.5Kx86) →
Kubota KX040-4 Specs
| Class | 4-ton mini excavator, conventional tail swing |
| Engine | 36 HP diesel |
| Operating weight | 9,460 lb |
| Bucket dig force | 10,200 lb |
| Dig depth | 12'10" |
| Aux hydraulic flow | 15.1 GPM |
| System pressure | 3,626 PSI |
A 4-ton machine with over 10,000 lb of dig force loads its tracks hard in the trench — the K-profile lug and 14" width are what keep it planted while the bucket does the work.
What replacement tracks cost
A heavy-duty TrackTECH 350x54.5Kx86 track for the KX040-4 runs $1,283.78 per track — continuously wound steel cord that prevents snapping under load, abrasion-resistant rubber that resists cuts and chunking in rocky terrain, directional tread optimized for trenching and digging traction. Tested to last 30% longer than standard aftermarket tracks, backed by our 24-month full replacement warranty. Free freight to the lower 48, same-day shipping before 12 PM CT. Replace in pairs — mismatched wear pulls a digging machine off line exactly when you need precision.
KX040-4 undercarriage parts (with Kubota part numbers)
While the machine is up on the blade, inspect the steel — new rubber on worn steel is money thrown away:
- Drive sprocket — #RD118-14433 ($190): hooked or sharpened teeth chew the drive lugs off a new track. At $190 it's cheap insurance for a $1,280 track.
- Front idler — #RD118-21300 ($539): check for flange wear and side play.
- Bottom roller — #RD118-21700 ($167): highest-wear item under the frame. Spin each one — seized or leaking means replace.
- Top roller — #RD411-22900 ($115): flat spots cause track slap on the return run.
Other Kubota minis — don't cross sizes
Browse all Kubota rubber tracks and undercarriage parts or jump to the KX040-4 collection.
When to replace KX040-4 tracks
- Lug depth under 50% — trenching traction drops first, especially in wet clay
- Exposed or rusting steel cord — structural failure is coming; replace before it strands the machine in a trench
- Cracking between lugs — normal aging past ~1,500–2,000 hours
- De-tracking that tensioning won't fix — stretched cords are permanent
FAQ
What size track does a Kubota KX040-4 use?
350x54.5Kx86 — 350 mm wide, 54.5 mm pitch, 86 links, K lug profile.
What does the K in 350x54.5Kx86 mean?
It's the Kubota-specific guide lug profile. A track with the same numbers but a different lug profile will not seat correctly on the KX040-4 undercarriage.
How much does a Kubota KX040-4 weigh?
About 9,460 lb operating weight — a 4-ton class machine with 12'10" dig depth.
How long do KX040-4 tracks last?
Typically 1,200–2,000 hours — dirt and turf extend life, rock and demolition shorten it.
Should I replace both tracks at once?
Yes. Mismatched wear affects tracking and accelerates wear on the new side.
Downtime costs more than tracks. Use the Rubber Track Finder or call (850) 816-7898 — we verify fitment by serial number before anything ships. Search. Select. Send.