Lippert 354176 Hydraulic Slide Actuator | 26" Stroke | 1-1/2" Bore

Replace a leaking, bent, or failed slide-out actuator with the Lippert Aluminum Hydraulic Actuator (Part 354176) — a 26-inch stroke, 1-1/2" bore replacement cylinder for Lippert hydraulic slide-out systems. Supersedes older part 128739. Available at The RV Surplus.

⚠️ CRITICAL — Confirm Fitment Before Ordering

Lippert makes hydraulic slide actuators in many stroke lengths and bore sizes. The correct actuator for your slide depends on the specific system, room weight, and slide design.

Consult your coach owner's manual or Lippert documentation for the correct fitting before ordering. An actuator with the wrong stroke won't fully extend or retract the room; wrong bore size won't develop the right force.

⭐ Key Specifications

⭐ Part Number History

Lippert 354176 is the current replacement for older part 128739. If your parts list or dealer quoted 128739, this is the correct supersession.

⚠️ Before Replacing the Actuator

Hydraulic slide problems aren't always the actuator. Rule these out first:

• Hydraulic fluid level — low fluid in the pump reservoir presents as a weak or non-moving slide
• Hose and fitting leaks — inspect every connection from pump to actuator; a weeping fitting looks like a bad cylinder
• Pump operation — confirm the pump builds pressure and reverses direction properly
• Battery voltage at the pump — hydraulic pumps need real current; a weak battery reads as a weak system
• Slide binding mechanically — if the room itself is dragging, a new cylinder won't fix the resistance
• See our RV Slide-Out Diagnostic Guide for a full walkthrough

⭐ When to Replace

Common signs the actuator itself is the fault:

• Visible fluid leak from the cylinder body or at the rod seal
• Bent or scored piston rod — any damage to the chrome rod surface tears the seal
• Slide extends but won't hold position (internal piston seal has failed, letting fluid bypass)
• Audible pump surge as the room moves — pump cycling to make up for internal leakage

⚠️ Professional Installation Recommended

Hydraulic slide actuator replacement involves working with pressurized hydraulic fluid, slide-mechanism alignment, and system bleeding. Should be performed by a qualified RV service technician unless you have prior hydraulic systems experience. Improper install can damage the slide, the pump, or both.

What's Included

• (1) Lippert 354176 aluminum hydraulic actuator, 26" stroke × 1-1/2" bore

NOT included: hydraulic fluid (standard ATF or Lippert-spec), hoses, fittings, mounting hardware if existing is damaged.

1-Year Warranty

Backed by Lippert's 1-year warranty. Check documentation for full terms.

Specifications

• Brand: Lippert
• Part Number: 354176
• Supersedes: 128739
• Hardware Type: Actuator (hydraulic cylinder)
• Material: Aluminum
• Cylinder Stroke: 26"
• Bore: 1-1/2"
• Application: Lippert hydraulic slide-out systems
• Shipping Dimensions: 60" L × 3.5" W × 3.5" H
• Shipping Weight: 8.5 lbs
• Country of Origin: USA
• Warranty: 1 year