Parts for your 1998 Toyota Hilux surf-Gas struts

1998 Toyota Hilux Surf Gas Struts — What They Do and When to Replace Them

Gas struts are relevant and factory-fitted on the 1998 Toyota Hilux Surf for the rear back door (liftgate). Toyota documentation refers to these as the “Back Door Stay Assembly”, listed in the Toyota Electronic Parts Catalog for the 185-series Surf (e.g., KZN185/RZN185/VZN185). The Toyota repair manual for the 1996–2002 Hilux Surf/4Runner family also details removal and installation of the back door stays. Note that the bonnet on this model uses a prop rod from factory, not gas struts.

On the Surf, the gas struts take the weight of the rear hatch, letting it lift smoothly and stay open without drama. Over years of use, the pressurised gas inside the struts slowly loses charge, seals harden, and cold weather can make weak struts barely hold up the door. That’s when the hatch starts drooping or needs a shoulder to keep it up — a good sign it’s time to replace them.

During servicing, it’s smart to give the back door struts a quick check. Open the hatch and see if it rises confidently and holds at full height. If the hatch sags, closes too quickly, or needs a hefty shove to get moving, the struts are tired. Also look for oily residue around the rod seal — that’s a giveaway the internal seal is leaking. Replacement is straightforward: support the hatch safely, pop off the retaining clips, swap the struts one at a time, and click them onto the ball studs. Match the new units to the original length and force rating (often stamped on the strut body). Genuine Toyota parts are catalogued as Back Door Stay Assemblies (example LH/RH part families commonly cited for the 185-series include 68960-xxxxx and 68950-xxxxx), and reputable aftermarket equivalents from brands like Stabilus or Monroe list direct-fit options for the 1996–2002 Surf/4Runner.

• Tell-tale signs they’re due: hatch won’t stay up, slow lift in cool weather, visible oiling on the rod, clunks at the hinge end.
• Good practice: replace in pairs to keep lift balanced