The Overland Series used 12V PA-01 mini linear actuators from Progressive Automations to build compact retractable side steps for Pegasus, a 1959 Land Rover Series II expedition vehicle. The system helps improve cabin access while preserving off-road ground clearance by deploying the steps when the doors open and retracting them below the body line when stowed.
| Creator | The Overland Series |
| Industry | Automotive/expedition vehicle |
| Location | Canada |
| Vehicle | 1959 Land Rover Series II, Pegasus |
| Application | Custom retractable side steps |
| Product Used | PA-01-4-56-N-12VDC |
| Key Requirements | Compact fitment, IP65 protection, fast deployment, 12V operation, field-serviceable relay control |
Who Is The Overland Series?
The Overland Series documents the complete ground-up engineering, restoration, and field testing of Pegasus, a 1959 Land Rover Series II built for long-distance expedition travel. The team is travelling the Pan-American Route from Canada to Argentina, where every vehicle system needs to balance modern convenience with rugged, field-serviceable reliability.
For this build, cabin access became a practical design challenge. Pegasus had upgraded seats and increased ride height, but fixed running boards were not a good match for remote off-road travel because they could reduce break-over clearance and catch on trail obstacles.
How Can Retractable Side Steps Preserve Off-Road Ground Clearance?
Retractable side steps can improve daily usability without permanently lowering the vehicle’s body line. When deployed, they provide a lower step-in point for the cabin. When retracted, they fold beneath the body to help preserve trail clearance.
For Pegasus, the step system needed to:
- Deploy automatically when the doors opened.
- Retract when the doors closed.
- Fit within tight chassis clearances.
- Avoid exposing delicate components to rocks and debris.
- Operate from the vehicle’s 12V electrical system.
- Remain simple enough to service in the field.
This made electric linear actuators a strong fit for the build because they could provide controlled push-and-pull motion in a compact format.
How a 12V Linear Actuator Powers the Retractable Side Steps
A 12V linear actuator can extend and retract from a vehicle electrical circuit when the system is designed for the actuator’s voltage, current draw, wiring protection, and control logic. In this project, the actuator’s job was to move the custom-fabricated step mechanism. The step structure itself still needed to carry the weight of the person using it.
The selected actuator was the PA-01-4-56-N-12VDC, which offered the specific force, speed, and stroke length to suit the needs of Pegasus. The PA-01 mini linear actuator is available in 12VDC and 24VDC configurations, with optional feedback, 1" to 40" stroke options, force options up to 225 lbs, IP65 weather protection, and built-in non-adjustable limit switches.
IP65 means the actuator is protected against dust and water ingress under rated conditions. For vehicle-mounted applications, IP protection should still be paired with smart placement, protected wiring, corrosion planning, and inspection access.
Why Was the PA-01 Mini Linear Actuator Selected for This Build?
The PA-01 was selected because the retractable step system required a compact mini actuator that could fit within tight chassis clearances while supporting the force, speed, stroke, and voltage requirements of the custom linkage.
The PA-01 was a practical match because it offered:
- Compact sizing for limited underbody space.
- 12VDC compatibility for vehicle integration.
- IP65 protection for dust and water exposure.
- Multiple stroke and force options.
- Built-in limit switches.
- Technical documentation for geometry planning.
For retractable vehicle side steps, actuator selection should be based on the step linkage, not step weight alone. The required force depends on step weight, pivot points, mounting angle, friction, and how the load changes through the full range of motion.
How Are the Linear Actuators Controlled by the Vehicle Door?
The retractable step system uses a simple 12VDC relay circuit instead of a complex microcontroller. Door-jamb switches trigger paired SPDT relays to reverse actuator polarity, allowing the actuators to extend when the door opens and retract when the door closes.
An SPDT relay, or single-pole double-throw relay, switches one circuit between two output paths. In a polarity-reversing actuator circuit, paired SPDT relays can change motor direction by reversing positive and negative connections to the actuator.
For off-road use, the system also included cab-mounted override switches. These allow the steps to stay locked in the stowed position during deep trail driving, crawling, or situations where step deployment could interfere with ground clearance.
What Should Builders Know About Force, Stroke, and Structural Load?
A linear actuator should move the step mechanism, not carry the standing load by itself. The step frame, pivots, brackets, and vehicle structure should support the person standing on the step.
| Requirement | What to Check | Why It Matters |
|---|---|---|
| Force | Step weight, linkage geometry, friction, and actuator angle | Prevents stalling or overload |
| Stroke | Distance the actuator must extend and retract | Stroke is not always equal to total step travel |
| Voltage | 12VDC or 24VDC system compatibility | Protects actuator and controls |
| Current draw | Fuse, wire gauge, and relay capacity | Prevents undersized wiring |
| Mounting | Bracket strength and alignment | Reduces binding and side loading |
| Environment | Dust, water, salt, debris, and road exposure | Helps determine protection needs |
| Override control | Manual lockout or cab-mounted switch | Prevents deployment during off-road driving |
What Was the Result of the Retractable Side Step Automation?
By integrating Progressive Automations actuator systems, Dan from The Overland Series created a retractable side step system that improved access to Pegasus while preserving the vehicle’s classic appearance and off-road capability.
The final system added modern convenience without relying on overly complex electronics. It also reinforced the value of using an actuator supplier that provides more than just hardware. Product documentation, CAD files, electrical specifications, and technical support all helped make the custom build easier to plan and execute.
“When you're hundreds of miles out on a trail, complex electronics can become a liability. Progressive Automations gave us both the rugged hardware and the precise technical documentation required to build an automated step system that is simple, durable, and easy to service in the field.”
Dan Bastiaansen
Owner and Founder, The Overland Series
Why Did The Overland Series Choose Progressive Automations?
Dan first discovered Progressive Automations while searching online for reliable actuator systems for a custom expedition vehicle automation project. Many online market options lacked the technical specifications, force ratings, CAD files, and wiring documentation needed for confident planning.
Progressive Automations stood out because the website provided detailed product information and CAD resources, while the support team helped answer technical questions during the planning stage. That combination helped Dan design the mechanism on the bench before fabrication.
For an off-grid vehicle travelling long distances from the nearest shop, clear documentation and serviceable components were not optional. They were part of the design philosophy.
How Do You Choose a Linear Actuator for Retractable Vehicle Steps?
For retractable side steps, start by defining the mechanism before choosing the actuator. A good actuator match depends on the full motion system.
- Measure available mounting space.
- Define the deployed and stowed step positions.
- Calculate required actuator stroke from the linkage geometry.
- Estimate force based on linkage load, not just step weight.
- Confirm voltage and current draw.
- Select proper fusing and wire gauge.
- Avoid side loading the actuator shaft.
- Protect wiring from abrasion, water, debris, and pinch points.
- Use brackets and pivots that carry structural loads.
- Include a manual override or stowed-position lockout for off-road use.
- Verify the actuator’s environmental rating against the real installation.
For custom vehicle builds, the best actuator is usually the one that fits the force, stroke, voltage, mounting, control, and serviceability needs of the mechanism.
Can Progressive Automations Help With Custom Vehicle Automation?
Custom expedition vehicle automation projects often require more than standard hardware. They need actuator solutions with the right force, stroke, voltage, speed, fitment, and environmental protection.
Progressive Automations supports builders, contractors, fabricators, and vehicle upfitters with electric linear actuators, mounting accessories, control options, product documentation, and technical support. For retractable steps, hatches, panels, lifts, storage systems, or other vehicle automation projects, explore specialty vehicle actuator solutions or contact Progressive Automations technical support team for assistance.
FAQ
What linear actuator should I use for retractable vehicle side steps?
Choose a linear actuator based on stroke, force, voltage, mounting space, environmental exposure, and control method. For this build, the PA-01-4-56-N-12VDC actuator was found to be the most suitable solution, but the exact model should be verified case-by-case depending on the requirements of each unique vehicle's retractable side steps.
How much force does a linear actuator need for retractable steps?
Required force depends on step weight, linkage geometry, mounting angle, friction, and the full range of motion. Do not size the actuator by step weight alone.
What stroke length is needed for an automatic vehicle step?
Stroke length depends on the linkage design. The actuator stroke is not always equal to the total step movement, so measure the actuator mounting distance in both the stowed and deployed positions.
Can I use a 12V linear actuator with a vehicle electrical system?
Yes, when the actuator is rated for 12VDC, and the circuit is designed for the actuator’s current draw. The system should include proper fuse protection, wire gauge, connectors, switches, and relays.
How do you make a linear actuator extend when a vehicle door opens?
A door-jamb switch can trigger a relay circuit. In this build, paired SPDT relays reversed polarity to extend the actuator when the door opened and retract it when the door closed.
Are linear actuators suitable for off-road vehicle applications?
Yes, when the actuator is selected for the load, environment, mounting geometry, and existing/planned control system. For exposed vehicle applications, review IP rating, wiring protection, bracket strength, debris exposure, and service access.
Should the linear actuator support the weight of someone standing on the step?
No. The step structure, brackets, pivots, and vehicle mounting points should support the standing load. The actuator should move the mechanism, not act as the main load-bearing structure.
How do you stop retractable steps from deploying during off-road driving?
Use a manual override or lockout switch. In this build, cab-mounted override switches allowed the steps to stay stowed during deep off-road crawling.
What is IP65 protection on a linear actuator?
IP65 is an ingress protection rating that indicates protection against dust and water exposure under rated conditions. It does not replace good installation practices, sealed wiring, corrosion planning, or inspection access.
Can I automate steps on a classic or vintage vehicle?
Yes, if the mechanism is designed around the vehicle’s structure, available mounting space, electrical system, and serviceability needs. This case study shows how a 1959 Land Rover Series II was upgraded with retractable side step automation while preserving its expedition-focused design.
Watch the showcase videos from The Overland Series on YouTube.