2018 Mazda CX5 Power Liftgate Not Staying Up: Strut Failure

Experiencing a sagging or uncooperative power liftgate on your 2018 Mazda CX-5 can be more than just an annoyance; it can be a safety concern. If your liftgate struggles to open fully, slowly closes on its own, or requires manual assistance to stay open, the most likely culprit is a failure of the hydraulic liftgate struts. These components are designed to assist the power motor and hold the heavy liftgate securely in the open position, and when they wear out, the power liftgate motor can be overworked, or the gate simply won't stay put.

What drivers notice on this 2018 Mazda CX-5

Owners of the 2018 Mazda CX-5 frequently report a specific set of behaviors when the rear power liftgate struts begin to fail. The most common complaint is that the liftgate, once opened, slowly drifts back down, sometimes hitting an unsuspecting head or making it difficult to load items. You might also notice the power liftgate motor sounding more strained than usual during operation, or the liftgate not opening to its full height. This issue is particularly noticeable in colder weather, as the hydraulic fluid inside the struts can become thicker, further reducing their effectiveness.

At a glance: difficulty, repair cost, and diagnostic workflow

• Difficulty Rating: 6/10 — Moderate
• Common Symptoms: The liftgate slowly closes on its own after being opened, even on level ground.; The liftgate fails to fully open to its intended height.; You need to manually push the liftgate open or hold it up to prevent it from closing.; The power liftgate motor sounds strained or makes groaning noises when opening or closing.
• Estimated Repair Cost: $100–$900 (parts + typical shop labor)
• OEM Tooling Required: Standard OBD-II scanner and hand tools

Diagnostic workflow:

1. Confirm the symptom on your vehicle.
2. Scan for stored or pending codes with an OBD-II tool.
3. Inspect the most common causes in this guide (visual checks first).
4. Run verification tests before replacing parts.
5. Repair, clear codes, and verify on a test drive.

Symptoms and warning signs

If your 2018 Mazda CX-5's power liftgate is acting up, pay close attention to these common symptoms:

• The liftgate slowly closes on its own after being opened, even on level ground.
• The liftgate fails to fully open to its intended height.
• You need to manually push the liftgate open or hold it up to prevent it from closing.
• The power liftgate motor sounds strained or makes groaning noises when opening or closing.
• The liftgate feels unusually heavy when you try to open or close it manually.
• Squeaking or creaking noises coming from the liftgate hinges or struts during operation.

How to verify and confirm the issue

Confirming that failing struts are the cause of your 2018 Mazda CX-5's power liftgate problem usually involves a few simple checks:

• Manual Push Test: With the power liftgate open (or as open as it will get), try to push it upwards with one hand. If it feels unusually heavy or offers little resistance, the struts are likely weak.
• Visual Inspection for Leaks: Carefully inspect the body of both liftgate struts. Look for any signs of oily residue or fluid leaks. A leaky strut indicates a loss of hydraulic pressure, meaning it can no longer hold the liftgate up effectively.
• Inspect for Damage: Check the strut rods for any bends, corrosion, or pitting. Also, examine the mounting points (ball sockets) for cracks, looseness, or excessive wear.
• Listen for Operation: Operate the power liftgate and listen for any grinding, clicking, or struggling noises from the motor or hinges. While not directly a strut issue, excessive strain on the motor can be a secondary symptom of failing struts.
• Compare to a Healthy Liftgate: If possible, compare the feel and operation of your CX-5's liftgate to another 2018 Mazda CX-5 that has a properly functioning power liftgate. This can help you gauge the difference in resistance.

Common causes (most likely first)

For the 2018 Mazda CX-5 power liftgate not staying up, the causes are almost always mechanical:

• Worn Hydraulic Struts: Over time, the seals within the hydraulic struts can degrade, leading to a loss of gas pressure or fluid. This is the most common reason for a liftgate to sag.
• Damaged Strut Mounts: The ball-and-socket mounts that connect the struts to the vehicle body and liftgate can wear out, crack, or become loose, affecting the strut's ability to function properly.
• Extreme Cold Weather: While not a cause of failure, very cold temperatures can temporarily thicken the hydraulic fluid inside the struts, making them less effective until the vehicle warms up.
• Impact Damage: A rear-end collision or impact to the liftgate area could damage the struts or their mounting points.

Related guides on this vehicle

• P0011 2024 Lexus Gx: Intake Camshaft Timing Over-Advanced
• AC Not Cold Enough 2018 Toyota Rav4: Fix Warm Air
• Driver Side Power Window Won't Go Up 2018 Toyota Land Cruiser

Step-by-step diagnosis and fixes

Addressing a failing power liftgate on your 2018 Mazda CX-5 primarily involves replacing the worn-out struts. Here’s a general workflow:

1. Confirm Strut Failure: Perform the verification steps mentioned above to ensure the struts are indeed the problem.
2. Gather Tools and Parts: You'll need new liftgate struts specific to your 2018 Mazda CX-5 (ensure they are for a power liftgate, as they can differ from manual ones), a socket set, a flathead screwdriver or pry tool, and a sturdy prop rod or a helper to hold the liftgate open.
3. Secure the Liftgate: This is critical for safety. Have a helper hold the liftgate firmly, or use a strong prop rod to keep it securely open. The liftgate is heavy and can cause injury if it falls.
4. Remove Old Struts:
   • Locate the mounting points of the struts. There's typically a clip on each end of the strut's ball socket.
   • Use a small flathead screwdriver or pry tool to carefully pry up the retaining clip on the upper mounting point.
   • Once the clip is released, gently pry the strut end off the ball stud.
   • Repeat the process for the lower mounting point.
   • Remove the old strut.
5. Install New Struts:
   • With the liftgate still securely held, start by attaching one end of the new strut (usually the upper end first, but check instructions).
   • Simply push the new strut's ball socket onto the ball stud until it clicks into place. The retaining clip should snap back automatically.
   • Repeat for the other end of the strut.
   • Install one strut at a time. It's often easier to install the bottom first, then the top, as the strut will be compressed slightly.
6. Test Operation: Once both new struts are installed, carefully remove the prop rod or release your helper. Operate the power liftgate slowly, checking that it opens fully and holds itself securely in the open position. You may need to cycle it a few times for the new struts to settle.

For more general repair guidance, you can always check our All repair guides.

Repair options and cost factors

When your 2018 Mazda CX-5's power liftgate struts fail, you have a few repair options, each with different cost implications:

• DIY Replacement: This is the most cost-effective option if you're comfortable with basic hand tools. You'll only pay for the parts, which typically range from $75 to $150 per strut, so $150–$300 for a pair of quality aftermarket struts. Ensure you get struts designed for a power liftgate system.
• Independent Repair Shop: An independent mechanic can perform this repair for you. Expect to pay for parts plus 1-2 hours of labor, typically totaling $250–$400.
• Mazda Dealership: Dealerships will generally charge the highest rates for parts and labor. The total cost could range from $350–$600 or more, but you'll benefit from OEM parts and specialized Mazda technicians.

Cost factors include the brand and quality of replacement struts (OEM vs. aftermarket), regional labor rates, and whether any other components (like damaged mounts) need replacement.

When to see a professional

While replacing liftgate struts is a relatively straightforward DIY task for many, there are times when it's best to consult a professional technician for your 2018 Mazda CX-5:

• Uncertainty: If you're unsure about the diagnostic process or uncomfortable working with a heavy liftgate.
• Other Symptoms: If the liftgate issue is accompanied by unusual electrical problems, error messages, or if the power liftgate motor itself seems to be failing (e.g., no movement at all, not just sagging).
• Lack of Tools/Helper: If you don't have the necessary tools or a reliable helper to safely support the liftgate during the repair.
• Damage Beyond Struts: If you notice damage to the liftgate hinges, wiring, or the power liftgate motor assembly, which might require more complex repair.

For more information on your specific model, you can visit our Mazda CX-5 model hub.

Frequently asked questions

Can I drive my 2018 Mazda CX-5 with a failing liftgate strut?

Yes, you can drive your 2018 Mazda CX-5 with failing liftgate struts, but it's important to exercise caution. The main risk is the liftgate falling unexpectedly when open, which can cause injury. Always be mindful when opening the liftgate and consider propping it open if you need to access the cargo area.

How long do liftgate struts typically last on a Mazda CX-5?

Liftgate struts on a Mazda CX-5, like most vehicles, typically last between 5 to 10 years or 50,000 to 100,000 miles, depending on usage and environmental conditions. Frequent opening and closing, especially in extreme temperatures, can shorten their lifespan.

Are the power liftgate struts different from manual ones for a 2018 Mazda CX-5?

Yes, the struts designed for a 2018 Mazda CX-5 with a power liftgate are often different from those for a manual liftgate. Power liftgate struts are typically engineered to work in conjunction with the electric motor and may have different damping characteristics or force ratings. Always ensure you purchase the correct struts for your specific vehicle's liftgate type.

Sources and further reading

• Browse vehicles
• Mazda vehicle hub
• Owner's Manual for 2018 Mazda CX-5

This article is intended for informational purposes only and is not a substitute for professional automotive advice or OEM service procedures; always consult a qualified technician for safety-critical work.

Explore related guides on ClearTheCode

• Browse OBD-II codes
• All repair guides