CATHydraulic Parts

1003259 Pump Gr-Piston — Cat 416B 426B

This is a high-quality piston pump designed to generate hydraulic flow and pressure for the main operating systems of heavy equipment. It is manufactured to meet stringent OEM standards, ensuring superior durability and performance compared to worn or failing units that exhibit reduced flow or internal leakage. Operators may notice sluggish hydraulic functions, decreased lifting capacity, or erratic boom/bucket movements when this pump begins to fail.

Pump Gr-Piston – Part No 1003259 – CAT Spare Part
Part Specifications
BrandCAT
CategoryHydraulic Parts
ConditionAftermarket — OEM Specification
DispatchSame-day from Mumbai (before 3 PM IST)
GST InvoiceAvailable — all orders
Export DocsCommercial invoice, packing list, COO

Compatible Models

Always verify with serial number before ordering.

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Full shipping information on regional pages · Air freight 2–12 days · GST invoice for India

Installation & Application Notes

Flush hydraulic lines before fitting new components. Use only manufacturer-specified hydraulic fluid. Check O-rings and backup rings for correct orientation. Bleed air from system after installation.

Always consult the OEM service manual for model-specific torque values and procedures. WhatsApp our technical team if you need fitment guidance.

Part TypePiston Pump
MaterialHardened steel and cast iron
ApplicationMain hydraulic system
Service LifeReplace every 4,000 hrs or as needed
CompatibilityOEM specification
ConditionNew — CTP aftermarket replacement

Failure Symptoms

Initial signs of a failing piston pump include a noticeable decrease in hydraulic system performance, such as slower implement speeds. If ignored, the pump's efficiency will continue to degrade, leading to inconsistent operation and potential overheating of the hydraulic fluid. Continued operation with a severely worn pump risks damage to other hydraulic components due to insufficient lubrication and increased particulate contamination.

Installation Tip

Ensure the hydraulic reservoir is clean and the fluid level is correct before installation; avoid overtightening mounting bolts, as this can distort the pump housing and cause premature failure.

Service Note

Inspect hydraulic filters and fluid for signs of metal debris, which could indicate internal pump wear.