How to Safely Remove the Trunk Lift Support on a Heavy Duty Towing Rig

Trunk lift supports—gas struts—hold open the heavy deck lids and storage compartment doors on heavy duty towing rigs. On a tow truck, these components carry far more load than the struts on a passenger car, and they store enough energy to cause serious injury if released carelessly. Whether you're replacing a blown strut or gaining access to the compartment behind it, the removal process demands deliberate steps: isolate the energy, support the lid, and control the strut from the moment the retaining clips come free. This guide covers the tools, sequence, and handling practices that keep the job safe and predictable.

<h2>Understand the Risks Before You Start</h2>

A gas strut is a sealed cylinder containing pressurized nitrogen pushing against a piston rod. The pressure can range from a few hundred to well over 1,000 newtons—enough to extend the rod forcefully the instant it's released. That stored energy is the primary hazard, but it isn't the only one.

<ul>

<li>Stored pressure: A strut that has failed or is still charged can extend violently when a mount is disconnected.</li>

<li>Falling lids: A tow rig storage lid can weigh 30–60 pounds or more. Once the struts are off, nothing holds it open.</li>

<li>Pinch points: The hinge line, the strut body, and the compartment lip can crush fingers and hands during collapse.</li>

<li>Sudden failure: Worn ball sockets and corroded brackets can shear under load, releasing the lid without warning.</li>

</ul>

Treat every strut as fully pressurized until it's confirmed otherwise. Never assume a strut is "dead" just because it no longer holds the lid.

<h2>Tools, Preparation, and Lid Support</h2>

Do the job on level, hard ground with the parking brake set and the wheels chocked. If the rig has an air suspension or hydraulic systems, lower and depressurize it per the manufacturer's procedure so the chassis doesn't shift mid-job.

Tools to have on hand:

<ul>

<li>Safety glasses and cut-resistant gloves</li>

<li>A thin flathead screwdriver or a dedicated clip-removal pick</li>

<li>A small socket set and open-end wrenches sized to the ball stud nuts</li>

<li>A pry bar or trim tool for stubborn retaining clips</li>

<li>A prop rod, wooden block, or an assistant to hold the lid</li>

</ul>

Support the lid first. Open it fully and place a prop rod or wood block between the lid and the compartment frame. On heavy deck lids, use two supports—one at each corner—so the load is balanced. Never rely on the struts themselves to hold the lid while you work.

If the strut is powered or tied into a body control module, disconnect the battery ground before touching the wiring. This prevents a compartment light or actuator from energizing while your hands are inside the mechanism.

<h2>Step-by-Step Removal Procedure</h2>

Work one strut at a time, and keep both hands on the component throughout.

<ol>

<li>Mark the orientation. Note which end is the body and which is the rod, and photograph the mounting points. Reinstalling a strut backward can damage the seal.</li>

<li>Open the lid and install your supports. Confirm the lid cannot drop before you continue.</li>

<li>Clean the mounting area. Dirt and rust around the ball sockets make clips harder to release and can hide corrosion damage.</li>

<li>Release the upper mount first. Slide a pick or thin screwdriver under the retaining clip and pry it off, or remove the nut and washer on a stud-style mount. Keep a firm grip on the strut body with your free hand.</li>

<li>Support the strut, then release the lower mount. The strut will still be partially charged, so control it as the second clip comes free. Let it extend slowly rather than letting it snap out.</li>

<li>Lower the lid. With the strut removed, the lid has no counterbalance. Lower it slowly with your support or an assistant, or prop it open if you need the space clear.</li>

<li>Repeat on the opposite side if you're replacing both struts.</li>

</ol>

Practical tips:

<ul>

<li>If a retaining clip is seized, apply penetrating oil and wait ten minutes rather than forcing it—bent clips can damage the ball stud.</li>

<li>Compress a strut slightly by hand before releasing the second mount; this reduces the extension force at the moment of separation.</li>

<li>If the rod is bent or the body is oily, the strut has failed internally. Handle it as a pressurized part regardless.</li>

<li>Keep the lid's hinge hardware tight. A loose hinge lets the lid shift and jams the strut during removal.</li>

</ul>

<h2>Handling, Disposal, and Replacement Notes</h2>

Once removed, a gas strut is still a pressurized vessel.

<ul>

<li>Do not puncture, crush, heat, or incinerate a strut.</li>

<li>Do not store it loose in a toolbox where the rod can be struck and extended.</li>

<li>Store removed struts rod-down if possible, and keep them away from sparks and open flame.</li>

<li>Recycle them at an auto parts store or a household hazardous waste facility that accepts gas springs.</li>

</ul>

When replacing, match the original specifications: extended length, compressed length, stroke, force rating in newtons, and end-fitting type. A lower-force strut won't hold a heavy tow rig lid; a higher-force strut can warp the mounting brackets or make the lid hard to close. Replace both struts at the same time so the lid stays balanced.

<h2>Conclusion</h2>

Removing a trunk lift support from a heavy duty towing rig comes down to control: support the lid, isolate the stored energy, and release each mount with a firm grip on the strut. Work on level ground, use the right clip tools, and never trust a strut to hold a lid on its own. Follow that sequence, and the job stays quick, clean, and safe.