What gas struts actually do in a rooftop tent

Gas struts — also called gas springs or gas lifts — are pressurised cylinders that store mechanical energy and release it as controlled, progressive force. In a hardshell rooftop tent, they do two jobs: assist the opening lift so the lid doesn't require full manual effort, and control the closing speed so the shell doesn't slam down.

The strut rating has to be matched to the weight of the lid — including any gear mounted on top. A tent carrying a solar panel and rack needs struts calibrated for that total load. Too light and the lid won't stay open under weight. Too heavy and the lid becomes difficult to close. This calibration is one of the more important and often overlooked aspects of tent setup.

Where the strut sits — inside or outside the shell — is a separate question from how well it performs. Both placements can produce excellent lift characteristics. The differences show up in other areas.

The case against external struts — and why most of it doesn't hold up

Concern 1: They'll rust

This is the most common objection and the one with the least substance behind it when quality components are used. Stabilus — one of the most widely specified gas strut brands in the RTT category — is the same manufacturer whose struts are fitted under the bonnet of Toyota Land Cruisers, including the 150 Series Prado. Underbonnet is arguably one of the harshest environments a gas strut can operate in: extreme heat cycles, oil mist, road debris, and no UV protection to speak of. Those struts last the life of the vehicle without issue.

An external RTT strut sits in open air on the side of the tent — exposed to weather but not to engine heat, and not in a sealed environment where moisture accumulates. The painted body finish on a quality Stabilus strut is more than sufficient for this application. Stainless steel struts get marketed as an upgrade in some circles, but stainless is not a simple improvement — it can still develop surface staining in salt environments, and the cost premium doesn't reflect a meaningful real-world durability gain over a quality painted strut in typical Australian touring conditions.

In years of use and looking at used tents on the secondhand market, the worst case for external struts is some surface oxidation on older examples that have seen significant exposure without any maintenance. It's a cosmetic issue, not a functional one, and it's the kind of thing that affects any steel component on a touring vehicle eventually.

Concern 3: They'll snag on tree branches

The argument is that an external strut sitting proud of the tent side is a snag point for overhanging branches on tight tracks. In practice, think about what else is already mounted on the side of a touring vehicle — an awning, a shower tent, Maxtrax, a shovel, a spare wheel, a hi-lift jack. Any of those presents a significantly larger and more exposed snag profile than a gas strut sitting close to the tent shell. If you're navigating tight scrub and something is going to catch, it won't be the strut. The concern doesn't hold up against what a typical touring setup actually looks like from the side.

Concern 4: They block awning mounting

This is a legitimate practical consideration — but it's a solved problem with the right hardware, not an inherent limitation of external struts. A Revo-X Stabilus strut sits approximately 35mm proud of the tent side. The Revo-X awning bracket is laser-cut in Australia specifically to clear that strut profile, providing 40mm of clearance between the bracket and the strut body. The awning mounts cleanly over the strut without modification, contact, or compromise.

The issue only arises when people try to run generic or non-matched accessories that weren't designed around the specific strut geometry. Purpose-built brackets for the tent you're running eliminate this entirely.

A design note: strut placement and side door access

This one applies regardless of whether you're evaluating external struts specifically — it's a placement and design quality issue. On some tent models, the strut is positioned in a way that partially obstructs the side canvas door or window opening. Getting in and out means working around the strut body rather than having a clear path through. A well-designed tent positions the strut rearward of the side entry so that opening is fully unobstructed. When evaluating any tent, open the side door fully and check whether the strut sits clear of that opening or cuts into it.

A related consideration applies to awning pole placement. On some setups, the 3rd or 4th awning pole on each side ends up positioned directly in line with the tent's side entry point — meaning you're stepping between poles every time you get in or out while the awning is deployed. It's a detail that doesn't come up in spec sheets but matters every single time you use the tent. Side entry clearance, strut position, and awning pole spacing are worth checking together as a system, not in isolation.

The case against internal struts — the points that rarely get discussed

They can cost you interior space

A gas strut body has physical width. When struts are routed internally, they have to fit within the perimeter of the shell — between the seal line and the canvas. On some tent models, the internal shell wall has to be designed around the strut profile, which can push inward into the usable interior and reduce the effective mattress footprint. On others, the tent footprint has to be made larger to compensate — which means more weight and more cost.

On some models, ceiling height constraints inside the shell mean the strut has to be undersized relative to the lid weight — a compromised strut rating to make it physically fit. On others, multiple smaller struts per side are used to achieve the required lift force where a single correctly-rated external strut would do the job. These are real design trade-offs that internal routing creates and external routing simply avoids.

The corrosion risk nobody talks about

This is the more significant concern, and it's almost never mentioned in marketing content. Internal struts sit inside a sealed enclosure. If any moisture gets past the seal — whether from condensation, minor ingress during a wet trip, or the heat-cycling of humid air over time — it creates a contained, moist environment around the strut body and its mounting hardware. That's a fundamentally worse environment than open air.

Heat cycling makes it worse. A black alloy shell in Australian summer sun gets very hot. When the tent cools overnight, that air contracts and if moisture is present it deposits on the coldest internal surfaces — including the strut body and its fasteners. Repeat this hundreds of times over a few years of regular use and you have a slow-building corrosion problem that's invisible from the outside and difficult to access for inspection or treatment.

This isn't theoretical. It's been observed on real-world enclosed designs where internal hardware including strut bodies and mounting fasteners have developed heavy rust, paint loss, and corrosion that contaminated the interior. By the time it's visible, the damage is already significant and the hardware is difficult to reach for maintenance or replacement.

What to look for regardless of strut placement

The strut placement debate can distract from the questions that matter more for long-term reliability:

• Brand and rating — a named manufacturer with a known cycle rating and replacement parts availability matters far more than placement. Generic unbranded struts are the real risk category, not external placement.
• Load matching — struts must be rated to the actual deployed weight of the lid including any roof-mounted gear. A mismatch causes either a lid that won't hold open or one that's difficult to close safely.
• Mounting hardware quality — the bolts, brackets, and pivot points that attach the strut to the shell see significant dynamic load over thousands of open/close cycles. Stainless fasteners at mounting points are more justified than stainless strut bodies in coastal or high-humidity environments.
• Parts availability — can you identify who manufactured the strut? Does the brand stock replacements directly and ship them quickly? A named manufacturer with standard sizing means you're not dependent on a single supply chain. An unbranded strut with no supplier information is a risk that doesn't show up until you need a replacement five years from now.
• Replaceability — can you get a replacement strut in five years? Is it a standard size from a major manufacturer, or a proprietary part you'd need to source through the original brand?
• Accessory compatibility — if external, do purpose-built mounting brackets exist for the awning and accessories you plan to run? If internal, what's the actual internal mattress dimension, not just the shell footprint?

How the Revo-X approaches this

The Revo-X uses external Stabilus gas struts. The decision comes down to three things: interior space, serviceability, and proven component performance.

Keeping the struts external means the full internal perimeter of the shell is available for mattress footprint — nothing is compromised by routing hardware through the walls. The 1,130mm × 1,970mm mattress reflects the usable interior, not a nominal shell size that sacrifices space to accommodate internal components.

Serviceability is straightforward — the struts are accessible, inspectable, and replaceable without disassembly. Stabilus is a brand with decades of automotive and industrial application behind it, with standard sizing and replacement availability that won't depend on a single supplier.

The awning compatibility concern is addressed with purpose-built laser-cut brackets that clear the strut geometry with 40mm of space. If you're running a Revo-X awning, this is already accounted for. If you're running a third-party awning, the bracket solution is straightforward — contact us and we'll work through the mounting geometry with you.

Replacing a gas strut — what to know before you start

Gas struts are under significant pressure even when fully extended — but they are at their most dangerous when fully compressed, meaning the lid is closed. A strut being removed in the closed position has maximum stored energy and will extend with significant force if released incorrectly. This is a job worth doing carefully, or having done by someone with experience.

The safest approach is to replace one strut at a time, with the tent in a controlled position. On the Revo-X specifically, unzipping the canvas from around the top shell allows the lid to travel slightly higher than its normal open position — this partially unloads the strut, reducing the force it's holding when you disconnect it. Even then, do one side at a time and have a second person supporting the lid. Stabilus struts on the Revo-X click on and off at their mounting points — the disconnection itself is straightforward, but it's the stored pressure in a fully loaded strut that demands respect.

Never attempt to remove both struts simultaneously with the lid open. Never try to compress a strut by hand to remove it under load.

Questions about strut setup or awning compatibility on your Revo-X?

If you're working through accessory compatibility or want to talk through the mounting geometry for a specific awning or rack setup, get in touch directly.

• Email: sales@raingersupplyco.com.au
• Revo-X product page: Revo-X 1.3 | Revo-X 1.45