A cabin mount (also called a cabin cushion or cab isolator) is a rubber-to-metal bonded vibration isolator placed between the cab structure and the machine's main frame. It prevents harmful whole-body vibration from reaching the operator while supporting the full cab weight under dynamic loads.
Part 17A-54-46120 is the OEM-specified replacement for:
Often used alongside the Komatsu 17A-54-46130 Komatsu Cabin Cushion, which serves the same function on Komatsu D51 Series.
Further reading: vibration isolation — Komatsu machinery — natural rubber.
All specifications reflect Komatsu OEM data produced under ISO 9001:2015 quality management.
| Part Number | 17A-54-46120 / 17A5446120 |
|---|---|
| Brand | Komatsu |
| Part Type | Cabin Mount Cushion |
| Weight | 6.80 kg |
| Material | High-elastomer rubber + steel insert |
| Mounting | 4-bolt pattern |
| Temperature Range | -40 deg C to +80 deg C |
| Hardness | >= 45 Shore A |
| Tensile Strength | >= 14 MPa |
| Compression Set | <= 25% (22h/70 deg C) |
| Certification | ISO 9001:2015 |
Aftermarket alternatives frequently deviate from OEM durometer, compound formulation, and dimensional tolerances — causing premature failure. Babacan Kaucuk supplies only ISO 9001:2015-certified OEM-quality parts.
How do I know my cabin mount needs replacement?
Signs include increased cab vibration and noise, visible rubber cracking, cab sitting lower or at an angle, or failed bounce test (cab doesn't return to center after pushing).
Can I use aftermarket cabin mounts?
Generic aftermarket mounts often differ in durometer (Shore A hardness) and rubber compound. This causes early failure or inadequate isolation. Use OEM-spec parts.
What torque should I use?
Refer to your machine's service manual for the specific torque value. Typically 120–180 Nm for M16 bolts, but always verify with the OEM data.
Are all Komatsu cabin mounts interchangeable?
No. Each part number is engineered for a specific load range and geometry. Cross-referencing must be confirmed in the parts catalog for your serial number.
ISO 9001:2015 certified OEM-quality parts. Ships from Ankara. 24-hour quote worldwide.
OEM cabin mounts for Komatsu heavy equipment are formulated from natural rubber (NR) or styrene-butadiene rubber (SBR) compounds reinforced with carbon black for dynamic fatigue resistance. Hardness is specified at 40–55 Shore A (ASTM D2240) to deliver the correct balance between vibration isolation effectiveness and static load support under cab weight. Lower Shore A values (40–45) favour vibration attenuation in high-vibration applications such as dozer and grader cabs; higher values (50–60) suit machines where cab stability under slope operation is critical.
Compression set is a critical durability property. OEM specifications require compression set below 25% after 22 hours at 70°C, tested per ASTM D395 Method B. High compression set causes the cab to sit lower over time, losing the designed vibration isolation gap and creating metal-to-metal contact risk at maximum deflection. Tensile strength (ASTM D412 Die C) exceeds 12 MPa and elongation-at-break exceeds 350% in compliant OEM mounts, ensuring the rubber bond resists dynamic tensile loads during cab pitching and rolling on uneven terrain. Ozone resistance (ASTM D1149) prevents surface crazing in outdoor environments where UV and ozone levels are elevated.
Generic aftermarket cabin mounts routinely fail to meet these compound requirements. Deviations of even 5 Shore A points from the OEM specification measurably affect the vibration transmissibility curve, shifting the system resonance frequency and reducing isolation effectiveness at the machine dominant vibration frequency. For operator health (ISO 2631-1 WBV exposure limits), correct mount specification is not a comfort feature — it is a regulatory compliance and occupational health requirement.
Cabin mounts on Komatsu heavy equipment should be visually inspected every 250 operating hours. The inspection covers: rubber surface condition (accept fine surface crazing under 0.5 mm depth; reject any open cracks), cab height measurement at each mount position compared to the reference specification to detect progressive compression set, and a cab bounce test (push the cab firmly downward at the centre and release — it must return to the neutral position within two oscillation cycles).
Replacement interval: 4,000 hours or 4 years, whichever comes first, under normal operating conditions. Replace immediately upon: any visible rubber cracking, cab height below nominal by ≥5 mm, bounce test failure, or after any cab rollover event regardless of visible damage. Always replace the complete set of mounts simultaneously — never mix new and old mounts on the same machine, as the difference in spring rate creates cab lean and uneven load distribution on the new mounts.
Conditions accelerating degradation: sustained operation above 40°C ambient (Middle East, Australia summer), hydraulic oil spills on rubber surfaces (causes swelling and softening), and altitude above 3,000 m (elevated UV and ozone concentration accelerate surface oxidation). In these conditions, reduce the inspection interval to 125 hours.
Part number 17A-54-46120 is the Komatsu OEM designation and primary search identifier for this component. In Komatsu parts catalogs it may also appear as 17A5446120 (condensed form without hyphens) or under a supersession number in more recent catalog editions. A supersession number indicates a revised or improved replacement — both numbers refer to the same installation position and either can be ordered.
Cross-referencing from aftermarket catalogs requires caution: generic catalogs match by application but do not guarantee dimensional compliance, rubber durometer, or material compound equivalence. A part that fits physically may still deviate from OEM spring rate, temperature rating, or fatigue life specification. For confirmed cross-reference support with your specific machine serial number, contact our parts team — we maintain Komatsu parts databases for all major model families.
What is whole-body vibration (WBV) and why do cabin mounts matter?
WBV is defined in ISO 2631-1 as acceleration transmitted through the seat and floor. Sustained exposure above 0.5 m/s² A(8) is linked to lumbar disorders. Cabin mounts are the primary mechanical filter reducing WBV from the machine frame to the cab structure — correct specification directly affects operator health and regulatory compliance.
What Shore A hardness should cabin mounts be for my machine?
For Komatsu equipment, cabin mounts are typically 40–55 Shore A (ASTM D2240). Softer compounds give better vibration isolation; harder compounds support higher static loads with more stability. OEM specifications balance both for your specific machine model and cab weight.
How do I measure compression set on a cabin mount?
Measure mount height at zero load and compare to the OEM new-part specification. Height reduction ≥10% of nominal indicates significant compression set — replace the mount. Measure all mounts and record results: uneven compression set across positions indicates uneven load distribution worth investigating.
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