Boom lift force dropping or hydraulic oil weeping from the rod on your 345D? A worn 389-1041 boom cylinder lets internal piston bypass bleed away lift force until the machine can no longer hold a loaded boom, while a scored rod seal leaks oil across the cylinder head. RITO supplies this heavy-duty replacement boom cylinder to restore full 345-series boom lift and clean, seal-tight operation.
Item NO.:
389-1041389-1041 Hydraulic Boom Cylinder Assembly for Caterpillar 345D, 349D, 349DL, 349D2 excavators. Heavy-duty double-acting boom cylinder with chrome-plated precision rod and a honed bore produced to OEM specification. Chrome layer thickness, honing surface finish and the multi-layer piston seal assembly are matched to the 345-class lifting duty cycle so the new cylinder delivers original boom holding force and cycle time from installation.
| Part Number | 389-1041 |
|---|---|
| Part Name | Hydraulic Boom Cylinder Assembly |
| Compatible Brand | Caterpillar |
| Applicable Models | 345D, 349D, 349DL, 349D2 Excavator |
| Application | Main boom lift hydraulic cylinder for Caterpillar 345-class excavators |
| Material | High-strength steel body, chrome-plated precision rod |
| Product Color | Yellow or industrial finish |
| Working Temperature | -25°C~+80°C |
| Key Function | Provides hydraulic boom lifting and holding force for 345-series excavator work cycles |
| Condition | 100% New Aftermarket OEM Quality |
| Packaging | Wooden Case Reinforced Carton Neutral Packing Customized Box |
Rod chrome layer thickness and adhesion matched to 345-series OEM specification, providing the hardness and corrosion resistance that determines boom cylinder seal service life.
Bore honed to OEM surface finish and dimensional tolerance for correct piston seal contact and low internal bypass at full 345 working pressure.
389-1041 covers the boom cylinder specification across the listed Caterpillar 345-class models, keeping fleets on one interchangeable replacement.
Rod and piston seal assembly rated for 345 maximum boom pressure, with buffer seals that protect the primary rod seal from pressure spikes during heavy lifts.
FAQ
Q: How do I tell if the 389-1041 boom cylinder has internal bypass or rod seal leakage?
A: External leakage is visible at the rod seal. Internal bypass causes slow boom drift when held stationary under load without visible external oil. Hold the boom at mid-stroke and watch for downward drift over 60 seconds.
Q: Can I replace only the seal kit in the 389-1041 cylinder?
A: If the rod chrome is undamaged and the bore is within specification, a seal kit repair is economical. Replace the full cylinder if the rod shows pitting, score marks or chrome delamination that would cut the new seals immediately.
Q: What bleeding procedure is needed after fitting 389-1041?
A: Cycle the boom slowly through full extension and retraction five times at low engine speed before applying full load. This purges air and seats the seal assembly before high-pressure operation.
Q: How to confirm 389-1041 is correct for my 345?
A: Match the existing cylinder part number against 389-1041 and confirm the machine model is one of: 345D, 349D, 349DL, 349D2. Provide the machine serial number for cross-reference confirmation.
Q: What quality options are available?
A: We provide original, OEM and high-quality aftermarket versions with stable supply capability.
Q:Why Choose RITO?
A:Listed Factory
Stable&Reliable Quality
OEM Factory for Chinese Top Excavator Brands
Supplier to Fortune 500 Companies
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