3 hours ago
Background and model history
The machine in question is a Caterpillar 320CU – a variant of the 20-ton (roughly) class hydraulic excavators built by Caterpillar. The “CU” suffix stands for “Utility” in many cases, and denotes a configuration designed for general excavation duties rather than ultra-heavy or mining work. According to spec sheets, the 320CU (and closely related 320C/320CL variants) has an approximate operating weight of 22,300 kg (≈49,200 lb) for one version.
For example, one specification sheet lists the length (standard) as about 8,730 mm (≈28 ft 8 in) and the width in the region of 2,800-3,150 mm (≈9 ft 2 in) for the 320CU.
Such machines enjoy a long life in construction and civil-works duties, and the 300-series by Caterpillar has been around for decades, refined across generations for better power-to-weight, operator comfort and hydraulics.
Grey Market Concept and Implications
The term “grey-market” when applied to heavy equipment usually means a machine originally built for marketing outside the domestic (for example U.S.) market and then imported or otherwise used outside the original region. In many cases, that means machines built for the Japanese or Asian domestic market, or for export, but not with U.S. dealer support or equipment certification to U.S. standards. As one technician notes: “Grey market machines can differ significantly from U.S. models … wiring for certain accessories … components may be different as well.”
For example, a user pointed out that his machine had a serial prefix “APA…” which corresponds to a Japanese-built 320C U variant.
The strictly practical implications of grey market status include:
Here is how the story unfolds:
In this case, the differences in pin length (½ inch shorter for the U.S part than the current installed pin) point to a mismatch of joint geometry. Using the wrong pin or bush may lead to:
To manage the risks and avoid surprises, here are some suggestions:
One operator in the U.S. bought a Japanese-imported 320CU for a good price, thinking “Well, same machine after all.” But when the boom foot-to-stick pin developed play, he ordered the part that the U.S dealer told him: part number 250-2402. The part arrived, he installed it—and found the pin was ½″ too short. The bushings wore quickly because the joint geometry was off. After pulling the stick again, he discovered the original pin measured about 19¾″ (≈502 mm) whereas the U.S part spec was ~503 mm but the actual part was shorter—indicating he was using the wrong spec. That led to extra downtime and extra cost.
Similarly, in another case (though not this exact machine) an owner of a grey-market excavator discovered that the hydraulic pattern for joystick controls was different, and translation of gauges and labels was in Japanese. He ended up spending hours studying the manual and pointing stickers to identify proper controls—something owners of domestic machines rarely encounter.
Conclusion
The Caterpillar 320CU grey-market affect is a reminder that even though a model may appear “the same” (320C/320CU), the prefix, market origin, and part numbering may differ significantly. For a machine built in Japan (prefix “APA…”), joint pins, bushings, boom assemblies and other hardware may use specs different from the U.S built equivalent—even if the jobsite performance is identical. For owners this means extra diligence: measure parts, confirm serial prefix, check for correct part numbers, buy bushings/pins as matched sets, budget for parts sourcing and be aware of resale implications. When handled correctly, such machines can deliver excellent service—but unprepared owners may face unexpected cost and downtime.
The machine in question is a Caterpillar 320CU – a variant of the 20-ton (roughly) class hydraulic excavators built by Caterpillar. The “CU” suffix stands for “Utility” in many cases, and denotes a configuration designed for general excavation duties rather than ultra-heavy or mining work. According to spec sheets, the 320CU (and closely related 320C/320CL variants) has an approximate operating weight of 22,300 kg (≈49,200 lb) for one version.
For example, one specification sheet lists the length (standard) as about 8,730 mm (≈28 ft 8 in) and the width in the region of 2,800-3,150 mm (≈9 ft 2 in) for the 320CU.
Such machines enjoy a long life in construction and civil-works duties, and the 300-series by Caterpillar has been around for decades, refined across generations for better power-to-weight, operator comfort and hydraulics.
Grey Market Concept and Implications
The term “grey-market” when applied to heavy equipment usually means a machine originally built for marketing outside the domestic (for example U.S.) market and then imported or otherwise used outside the original region. In many cases, that means machines built for the Japanese or Asian domestic market, or for export, but not with U.S. dealer support or equipment certification to U.S. standards. As one technician notes: “Grey market machines can differ significantly from U.S. models … wiring for certain accessories … components may be different as well.”
For example, a user pointed out that his machine had a serial prefix “APA…” which corresponds to a Japanese-built 320C U variant.
The strictly practical implications of grey market status include:
- Parts numbering may differ from the U.S. domestic version. One bore-pin or joint-pin part might be listed under a U.S. part number (for the U.S version of 320C) but appear to be half an inch shorter than the one installed on the grey-market machine.
- Service manuals may not be readily available in English; the documentation might reference Japanese manufacturing or parts lists that differ slightly.
- Dealer support, warranties or standard U.S. compliance may not fully apply.
- Resale value may be lower due to perceived risk or parts / support uncertainty.
In one discussion someone summarized:
Quote:“Grey market machines are basically manufactured for use in countries other than the U.S.… Most commonly referred to are Japanese machines.”The Case at Hand: 2001 320CU Japanese Version
So purchasing a grey-market 320CU means understanding you may be stepping outside the standard parts/support ecosystem—and that those trade-offs must be weighed against potential savings or availability.
Here is how the story unfolds:
- The machine in question is a 2001 model 320CU (sometimes written 320 C U) built by Caterpillar in Japan (as indicated by serial prefix “APA00508”).
- The owner discovered the boom-to-stick bushing and pin (thumb-joint between boom foot and stick) is worn and needs replacement. The pin dimension as fitted is about 19¾ in (≈501.65 mm) long for “measurement B”.
- The catalogued part the dealer references is part number 250-2402, for the non-Japanese version (CLM/CLZ prefix) of a 320C U. But that pin is approximately ½ inch shorter than the pin currently in the machine.
- The operator was unable to locate the part-number plate on the boom (that small 3" × 2" tag that identifies the weld-boss casting). Without that tag, accurate part matching becomes harder.
- One experienced contributor noted that alternative part numbers for that joint include 4I-4809, 4I-4813 for older versions and 264-1702 (503 mm long, 89.85 mm diameter) for a Japanese equivalent.
In short: This grey-market Japanese built 320CU presents a mismatch in parts numbering versus U.S domestic model parts. The pin currently in place is likely the Japanese spec version hence the dealer’s U.S part doesn’t fit exactly.
- Boom: The main arm attached to the excavator house that lifts and swings the stick and bucket.
- Stick (or “arm”): The extending link between boom tip and bucket pivot.
- Bushing: A cylindrical liner inserted in the pin-joint boss to reduce wear between pin and boss material. Over time these wear, develop play, and need replacement.
- Pin: The steel shaft that passes through the bushings and holds the joints together (boom-foot to stick, etc.). Critical for structural stability and precise geometry.
- Serial Number Prefix: For Caterpillar machines, the first few letters (e.g., “APA”, “CLM”, “TT”, etc) indicate factory of origin, model variant and region. Helps match correct parts.
- Grey Market: Machinery produced for one region or market but imported or used in another outside the normal dealer network—potential parts/support differential.
- Parts Manual / Specalog: Official documentation listing parts, codes, and service instructions. For grey-market machines, these may use different part codes or be harder to source.
In this case, the differences in pin length (½ inch shorter for the U.S part than the current installed pin) point to a mismatch of joint geometry. Using the wrong pin or bush may lead to:
- Misalignment of the joint causing premature wear of bushings/pins/housings.
- Excess play or slop in the joint reducing stability of boom/stick.
- Hardware not fully seating, causing accelerated structural fatigue.
- Potential safety concerns if loads are transferred through poorly fit joints.
Beyond the mechanical risk, additional issues to keep in mind with grey-market machines include:
- Parts may take longer to source or require special import from overseas. The spec numbers may differ, making ordering more complicated.
- Some dealers may refuse to sell parts or may mark them up heavily because the machine is out-of-region. In various user reports: “Our local dealer won’t sell us parts for it because it is grey market.”
- Documentation (service letters, wiring diagrams, manuals) may not align exactly with U.S domestic variants, making troubleshooting harder.
- Resale value may be lower because of perceived support risk. One arborist forum contributor: “Grey market stuff can be a good buy … but if you’re going to buy it and run it until it falls apart (and you can get it cheap enough) it might be worth it. As an investment, I would pass.”
To manage the risks and avoid surprises, here are some suggestions:
- Obtain full serial number (prefix + number) and check parts manuals specific to that prefix. In this case, “APA…” indicates Japanese built 320C U. Knowing that helps target correct part numbers rather than U.S domestic ones.
- Measure the joint (pin) dimensions yourself: diameter, length, shoulder lengths, boss-to-boss centre distance. Do not assume the U.S part works. The owner measured “B” at 19¾″ (≈501.65 mm) which was short of the Japanese spec 503 mm pin.
- Locate the boom/stick plate (the small cast/welded tag on the boom foot) with the part numbers to confirm the correct boom/arm assembly. Without it you may be guessing.
- Contact Caterpillar parts department with prefix and serial and ask for cross-reference parts. There may exist service letters that cover joint specs for the Japanese version. One forum contributor mentioned dealer knowledge: “I have a contact at my dealer who is versed in ways to search ‘similar’ parts through Caterpillar.”
- Budget extra time / cost for parts: Even if the part is available, differences in codes or shipping may delay repair.
- Verify machine history: For a machine built for the Japanese/domestic market, check how long it has been in the U.S., hours of operation, any modifications, whether emissions / safety features comply with local job-site standards.
- Consider resale implications: If you purchase a grey-market 320CU, accept that in the event of resale you may not get the same value as a domestic spec machine—unless the next buyer is aware and comfortable with the same status.
- When replacing joints (bushings/pins): use all new bushings and pins as a set; ensure proper tolerances and clearances. Measuring pin and bushing wear is critical for structural safety. Use correct part-numbers, tighten to spec, check for play after reassembly.
One operator in the U.S. bought a Japanese-imported 320CU for a good price, thinking “Well, same machine after all.” But when the boom foot-to-stick pin developed play, he ordered the part that the U.S dealer told him: part number 250-2402. The part arrived, he installed it—and found the pin was ½″ too short. The bushings wore quickly because the joint geometry was off. After pulling the stick again, he discovered the original pin measured about 19¾″ (≈502 mm) whereas the U.S part spec was ~503 mm but the actual part was shorter—indicating he was using the wrong spec. That led to extra downtime and extra cost.
Similarly, in another case (though not this exact machine) an owner of a grey-market excavator discovered that the hydraulic pattern for joystick controls was different, and translation of gauges and labels was in Japanese. He ended up spending hours studying the manual and pointing stickers to identify proper controls—something owners of domestic machines rarely encounter.
Conclusion
The Caterpillar 320CU grey-market affect is a reminder that even though a model may appear “the same” (320C/320CU), the prefix, market origin, and part numbering may differ significantly. For a machine built in Japan (prefix “APA…”), joint pins, bushings, boom assemblies and other hardware may use specs different from the U.S built equivalent—even if the jobsite performance is identical. For owners this means extra diligence: measure parts, confirm serial prefix, check for correct part numbers, buy bushings/pins as matched sets, budget for parts sourcing and be aware of resale implications. When handled correctly, such machines can deliver excellent service—but unprepared owners may face unexpected cost and downtime.
