Makita 419004-5 Spare Part - PISTON HR4011C/4001C

Original Makita piston 419004-5 — a precision‑machined metal piston for the percussion/impact assembly of SDS‑max rotary hammers that restores consistent blow force and smooth reciprocation.

This genuine Makita piston is a small but critical item among Makita parts used in the hammer assembly; it’s a direct, drop‑in replacement that stops loss of impact, irregular blows, and scoring caused by a worn piston.

Example fitment listings include HR4001C, HR4011C, HR4013C, DHR400 and HR4041C — use these model references to confirm compatibility with your tool.

The piston works inside a cylinder listed at about 28.5 mm and is supplied as the single metal piston component (part no. 419004-5) for the hammer mechanism.

Jump straight to the Makita spare parts diagrams:

• Makita DHR400 Parts
• Makita HR4001C Parts
• Makita HR4011C Parts
• Makita HR4013C Parts

Browse our full range of Makita hammer drill parts.