Case 850K Crawler Dozer: Specs, Parts & Common Issues
Produced 2004 – 2009, the Case 850K is the K-generation mid-large frame Case crawler dozer — Cummins 6BT-derived Tier 2/3 turbocharged six-cylinder diesel, hydrostatic dual-path transmission, and a substantially upgraded cab over the 850H predecessor. The 850K refined the H-generation hydrostatic platform with improved emissions calibration, a more capable operator station, and updated electronics — without the diesel particulate filter aftertreatment that came with the Tier 4 Interim 850L successor.
The Case 850K Crawler Dozer is the K-generation mid-large frame Case crawler dozer, produced from 2004 through 2009. The K-generation continues the hydrostatic dual-path drivetrain architecture introduced on the 850H and adds Tier 2/3 emissions compliance (production spans the Tier 2 to Tier 3 transition era), substantially refreshed operator station, electronic instrumentation, and improved sightlines to the blade. The 850K is the most refined hydrostatic 850 before the Tier 4 Interim 850L brought DPF aftertreatment service complexity.
For owners and operators today, the 850K is one of the most popular used-market 850-class machines: modern hydrostatic drivetrain, refined cab, broad Cummins 6BT-derived engine parts ecosystem, and no DPF service complexity. The H/K/L blade-carrier and operator-station cross-fits make 850K parts service straightforward.
At-a-glance specifications
Case 850K — factory specifications
- Production years
- 2004 – 2009
- Predecessor
- Case 850H (2000 – 2003)
- Successor
- Case 850L (2009 – 2014)
- Engine
- Cummins 6BT-derived inline 6-cyl turbocharged diesel, Tier 2 / Tier 3
- Displacement
- 359 cu in (5.9 L)
- Power
- ~145 – 160 HP flywheel (configuration dependent)
- Transmission
- Hydrostatic dual-path
- Emissions tier
- Tier 2 (early production) to Tier 3 (late production)
- Variants
- Standard, LT (Long-Track), LGP (Low Ground Pressure)
- Operating weight
- ~27,000 – 31,000 lb depending on variant
- Hydraulic system
- Load-sensing implement hydraulics, separate hydrostatic drive circuits
- Blade
- 6-way bulldozer blade — angle, tilt, lift hydraulically actuated
- Serial plate location
- Right side of cab platform, near operator entry
How the 850K differs from the 850H predecessor
- Tier 2/3 emissions compliance — production spans the Tier 2 to Tier 3 transition. Internal engine refinements for emissions calibration, but no DPF aftertreatment.
- Refreshed cab and electronics — improved HVAC, electronic instrumentation cluster, updated joystick control geometry, better visibility to the blade corners.
- Refined hydrostatic drivetrain calibration — same dual-path architecture as the 850H, with updated control software and refined charge pump configuration.
- Compatible blade-carrier hardware with 850H — most blade-carrier wear items (slider blocks, wear plates) carry forward from the 850H. Confirm by part number against your serial.
- Suspension seat — the 359121A1 suspension seat covers the 850K (along with 550H / 650H / 650K / 650L / 750K / 750L / 850H / 850L).
Variants: Standard, LT, LGP
The 850K shipped in three primary track configurations:
- Standard — standard-width track, balanced general dozing.
- LT (Long Track) — extended-length track frame for additional flotation and stability.
- LGP (Low Ground Pressure) — wider grouser pads with extended track frame for soft-ground / wetlands / agricultural-soil work.
Variant affects undercarriage parts. Confirm Standard vs. LT vs. LGP by serial before ordering.
Cummins 6BT-derived engine
The 850K continues the Cummins 6BT-derived inline six-cylinder turbocharged diesel engine lineage from the 850H, with Tier 2 / Tier 3 emissions calibration updates. Filters, injectors, water pump, alternator, and turbocharger components remain readily available through both Case dealer and aftermarket Cummins channels.
The Cummins 6BT industrial engine ecosystem is one of the deepest in the diesel-engine world. For 850K owners doing engine service or rebuild, the parts availability is a significant advantage. Browse the Case Dozer Parts hub for current 850K engine service kits.
Hydrostatic dual-path transmission
The 850K retains the hydrostatic dual-path architecture from the 850H — each track has its own variable-displacement pump and hydraulic motor, controlled by joystick. The K generation refines the control software and updates charge pump configuration.
Hydrostatic service items: charge pump, charge filter, hydraulic motor seals, drive pump bearings, control valve degradation. Hydraulic oil cleanliness is critical — the hydrostatic system is intolerant of contamination.
Blade-carrier and operator-station cross-fit
Many 850K wear items cross-fit with the 850H below and the 850L above. Notable confirmed cross-fits:
- The 117835A1 slider block and 117836A1 wear plate are documented mid-class Case dozer blade carrier cross-fit covering the H-generation family (550H, 650G, 650H, 750H, 850G, 850H) — the 850K shares the blade carrier architecture and uses the same wear hardware.
- The 359121A1 Case / New Holland dozer suspension seat with headrest covers the 850K (and 550H, 650H, 650K, 650L, 750K, 750L, 850H, 850L). One SKU covers nine machines.
Common 850K service issues
Hydrostatic transmission service
Same hydrostatic-system service profile as the 850H — charge pump, control valve, motor seal, oil contamination. Hydrostatic diagnosis usually requires dealer service tools for pressure testing.
Cummins 6BT-derived turbocharger wear
The turbocharger is a routine wear item on 15-plus-year-old engines. Symptoms: blue smoke at startup or under load, oil consumption climbing, audible whine outside the normal range, or visible shaft play.
Blade carrier wear plate replacement
The 117835A1 slider block and 117836A1 wear plate are routine blade-carrier service items.
Blade cylinder seal failure
Blade cylinder seal weep is normal at production-run age. Seal kit rebuilds address most cases.
Cutting edge wear
Cutting edge replacement is the most frequent blade-related service item.
Filter service interval
The hydrostatic drivetrain is intolerant of contamination. Stick to the recommended hydraulic filter and oil change intervals.
Cab electronics
The K-generation electronic instrumentation and joystick electronics are more sophisticated than the 850H — they can develop intermittent fault codes from connector corrosion or harness wear at production-run age.
Parts we carry for the Case 850K
| Part | Cross-fit | Notes |
|---|---|---|
| 359121A1 suspension seat | 550H + 650H + 650K + 650L + 750K + 750L + 850H + 850K + 850L | Single SKU covering nine Case dozers across H/K/L generations. |
| 117835A1 slider block | 550H, 650G, 650H, 750H, 850G, 850H, 850K | Mid-class Case dozer blade-carrier cross-fit (H-generation family). |
| 117836A1 wear plate | Same mid-class H-generation cross-fit | Pairs with the 117835A1 slider block. |
| Filter service kits | 850K-specific (Tier 2/3 Cummins 6BT-derived) | Engine oil, fuel, air, hydraulic filters. |
| Blade cutting edges & end bits | Mid-class dozer cross-fit | Standard or severe-duty cutting edges. |
| Blade cylinder seal kits | 850K-specific | Lift, angle, tilt cylinder seal kits. |
| Track undercarriage components | 850K-specific by variant (Std / LT / LGP) | Track pads, idlers, rollers, master pins by variant. |
| Hydrostatic system service parts | Charge pump, charge filter, drive components | Hydrostatic-specific service items. |
For the complete 850K parts inventory, browse the Case Dozer Parts hub.
Working on a Case 850K?
The 850K is the most refined “no-DPF” hydrostatic 850 — broad operator-station cross-fit with the H/K/L family and a strong Cummins 6BT-derived engine parts ecosystem. Our specialists can verify Standard vs. LT vs. LGP fitment by serial.
Mon – Fri, 7:00 AM – 5:00 PM CT
Request a PartWhere the 850K sits in the Case dozer family
The 850K is the K-generation mid-large frame Case crawler dozer, sitting between the Case 750K and the larger 1150K. Its predecessor is the Case 850H (Tier 1/2, original hydrostatic 850) and its successor is the Case 850L — which steps up to Tier 4 Interim emissions compliance with cooled EGR + DPF aftertreatment.
