JCB 3DX Hydraulic Cylinder Leaking: Seal Kit Checks
Applies to: JCB 3DX / 3CX / mid-size excavators
Quick answer
JCB 3DX Hydraulic Cylinder Leaking: Seal Kit Checks on JCB 3DX / 3CX / mid-size excavators: typical warning signs include Oil wet around rod gland; Slow cylinder extension under load. Common causes include Worn rod seal / wiper; Scored or bent rod. These notes identify parts to quote — they are not a certified repair procedure.
- Independent OEM-compatible supplier — not affiliated with JCB Ltd.
- Workshops typically RFQ: cylinder seal kit.
- Workshops typically RFQ: rod wiper.
- Workshops typically RFQ: O-ring kit.
- Workshops typically RFQ: hydraulic hose.
Warning signs
- Oil wet around rod gland
- Slow cylinder extension under load
- Visible scoring on chrome rod
- Boom or bucket drift when held
Common causes
- Worn rod seal / wiper
- Scored or bent rod
- Contaminated oil accelerating seal wear
- Incorrect seal profile after prior rebuild
Parts to quote
Typical line items workshops search next to this fault. Matched catalogue links go to a verified SKU when found; otherwise open search so you can RFQ by keyword. We confirm fitment before quoting.
FAQ
Should I replace the whole cylinder or only the seal kit?▼
If the rod and bore are undamaged, a correct seal kit often restores sealing. Deep chrome damage or bent rods usually need rod/cylinder replacement. Send photos of the gland and rod for fitment help.
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Confirm fitment & get a quote
Send machine model, hours, and part photos. We reply with availability, MOQ, and lead time in writing — no invented stock claims.