The Genie 128858GT is a genuine OEM Retaining Washer, M16 designed for Genie S-series telescopic boom lifts and Z-series articulating boom lifts. As a direct OEM replacement sourced through Genie's authorized parts network, this washer is manufactured to the exact material and dimensional standards required for these large-platform machines. Confirmed fitment includes the S-120, S-125, S-100, S-105, and Z-135/70 — some of the tallest and most demanding machines in the Genie lineup. Cross-reference part number 128858GT against your parts manual before ordering to ensure a correct match for your specific serial range.
Key Features
- OEM-Grade M16 Retention — Manufactured to Genie's exact material and hardness spec for M16 fastener applications, ensuring proper clamping load and washer integrity under heavy-duty cycle stress.
- Drop-In Replacement — Seats directly onto M16 hardware at the original mounting location, requiring no rework to the surrounding assembly.
- Broad Boom-Lift Fitment — Compatible with the S-100, S-105, S-120, and S-125 telescopic booms as well as the Z-135/70 articulating boom, covering Genie's largest platform-height models.
- Structural Load Distribution — A correctly spec'd retaining washer spreads fastener load across the mating surface; an undersized or worn washer can allow fastener migration and loosening in high-vibration structural joints.
- Safety-Critical Fastener Integrity — On large aerial boom lifts, structural joint fasteners directly affect platform stability and load integrity — using the correct OEM-specification washer supports safe, compliant operation at height.
A retaining washer serves as a load-spreading and locking interface between a fastener head or nut and the mating component surface. On large boom lifts like the S-125 and Z-135/70, structural connections experience significant dynamic forces during boom extension, rotation, and platform loading — making proper washer specification essential to maintaining joint tightness over time. When a retaining washer is missing, deformed, or of incorrect dimension, the fastener can work loose progressively, compromising the integrity of the joint and the safe operation of the machine.
Part Details
| Part Number | 128858GT |
|---|---|
| Brand | Genie |
| Part Type | Genuine OEM |
| Description | Retaining Washer, M16 |
Compatibility & Fitment
| Name | Model |
|---|---|
| S-120 | S-120 |
| S-125 | S-125 |
| S-100 | S-100 |
| S-105 | S-105 |
| Z-135/70 | Z-135/70 |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
