MARCH 07, 2025
Maxon Liftgate Cylinder Replacement for Dual Cylinder Tuck-Unders
Disclaimer: This guide is intended for informational or entertainment purposes only and should not be considered a substitute for professional mechanical advice or official manufacturer instructions. Liftgate repairs and maintenance, may result in serious injury, death, equipment damage, or operational failure, so always contact a professional repair facility near you to assess your specific needs.
Replacing a hydraulic cylinder on a truck lift gate is a critical maintenance procedure that requires careful attention to safety, component selection, and proper installation techniques. This guide outlines how we approach cylinder replacements based on our experience with Maxon tuck-under models using dual lift cylinders, such as Maxon Liftgate Cylinder 266037-01 and many others.
While the process applies broadly to Maxon’s GPT, GPTWR, GPTLR, and select TE models (TE-25DC and TE-33), it is not a substitute for official manufacturer guidelines nor a qualified repair facility that can assess your specific situation. Find a qualified option for liftgate repair near me to further inspect your specific situation and needs.
Hydraulic systems operate under high pressure, and improper installation can result in serious injury, equipment damage, or system failure. Always refer to Maxon’s official service documentation, follow workplace safety protocols, and consult a qualified technician if unsure about any step in the process.
This reference guide provides general best practices but does not cover every possible liftgate configuration or installation scenario. By proceeding with maintenance, you assume all associated risks and should always use OEM-approved liftgate parts to ensure safe and reliable liftgate operation.
- Finding the Correct Liftgate Cylinder
- Finding the Correct Pins for Your Lift gate Cylinde
- FAQ: Understanding Truck Lift Gate Cylinder Pins
- Step 1: Safety First – Preparing for Replacement
- Step 2: Removing the Old Cylinder
- Step 3: Installing the New Cylinder
- Step 4: Final Checks Before Powering On
- Finding Liftgate Repair Near Me
- Conclusion
Finding the Correct Liftgate Cylinder
For Maxon tuck-unders, while the America’s best selling cylinder is 266037-01, followed by 266038-01 and 266039-01, many other cylinders exist. To find the correct cylinder for your specific lift gate, visit our Maxon Liftgate Cylinder guide or reach out to our team for assistance in identifying the right part for your specific liftgate model.
Finding the Correct Pins for Your Lift gate Cylinde
When replacing a hydraulic cylinder on a liftgate, selecting the correct cylinder pins is just as important as installing the cylinder itself. The wrong pins—or a failure to grease them properly—can lead to premature wear, misalignment, or even liftgate failure, creating safety hazards and reducing the overall lifespan of the system.
Depending on the make, model, and year of the liftgate, cylinders may require different types of pins, including greasable, non-greasable, and stainless steel options.
Also note, that the upper and lower cylinder pins are not interchangeable. Installing the wrong type of pin, or reusing worn-out ones, can cause excessive wear on mounting points, improper cylinder movement, injury, and potential hydraulic misalignment, all of which may affect liftgate performance.
For this reason, always use OEM-approved pins designed specifically for the lift gate model in question. While aftermarket alternatives may be available, we do not recommend these as a solution since it goes against Maxon Liftgate’s best-in-class engineering standards, which can lead to misalignment, injury, or long-term operational issues. Ensuring that the correct pins are installed and properly greased during cylinder replacement is a crucial step in maintaining safe and reliable liftgate function.
If you’ve ever searched for Maxon liftgate parts near me or in your area, LiftGateMe is your solution. We can ship pins for any Maxon Liftgate Cylinder to your door– even if you need them for tomorrow’s job.
Excessive greasing and contamination can become a critical issue for your cylinder and its pins
FAQ: Understanding Truck Lift Gate Cylinder Pins
Many trailer and truck lift gate operators and technicians have questions about which pins to use when replacing a cylinder. Two common concerns include whether different pin types are available and whether the upper and lower pins are identical.
Yes, Maxon liftgate cylinders use greasable, non-greasable, and stainless steel pins, each with unique benefits depending on maintenance preferences and environmental conditions. Additionally, the upper pin and lower cylinder pin differ, meaning they must be installed in their designated positions to ensure proper liftgate operation.
By selecting the correct pin type and ensuring proper lubrication, operators can extend the lifespan of their hydraulic system, reduce wear, and maintain smooth liftgate performance.
Step 1: Safety First – Preparing for Replacement
Before starting, it’s essential to follow all safety precautions to prevent injuries and equipment damage. Hydraulic systems operate under high pressure, and improper handling can lead to serious injury.
✔ Lower the liftgate to the ground – This relieves hydraulic pressure and prevents sudden movement.
✔ Disconnect power – Remove the nut from the positive (+) battery terminal and disconnect the fused power cable to avoid accidental activation.
✔ Use jack stands when necessary – If the liftgate is on the ground, jack stands are not needed. However, if the gate cannot be lowered, jack stands must be used to support the framing of the gate (not the platform or cylinder) at the highest available point.
✔ Releasing hydraulic pressure – Once jack stands are in place, slowly open the pressure hoses on the cylinders to gradually relieve hydraulic pressure, allowing the gate system to rest firmly on the stands (one per side).
✔ Securing the cylinders – If replacing cylinders while the gate is raised, use stands under the cylinders or a securing strap (leather belt, heavy zip ties, etc.) to prevent them from crashing down when the pins are removed.
✔ Fluid management – Have drain buckets ready to collect any leaking hydraulic fluid when disconnecting hoses.
✔ Wear protective gloves and eye protection – Hydraulic fluid can be hazardous; always handle it with care.
✔ Check for leaks before starting – Inspect the cylinder and surrounding hydraulic lines for visible damage or fluid leaks.
✔ Keep bystanders clear – Ensure no one is standing under or near the liftgate during the process.
Step 2: Removing the Old Cylinder
The hydraulic cylinder is secured to the liftgate using Maxon-approved pins, which must be removed carefully. This step involves disconnecting the old cylinder while keeping the surrounding components intact.
✔ Locate the cylinder pins.
✔ Remove the existing pins –
* Remove the securing bolts that hold the cylinder mounting pins in place.
* Use a hammer and pin to punch out the old cylinder pins until the cylinder is free.
✔ Inspect the hydraulic hoses – Look for wear, cracks, or leaks before installing the new cylinder.
✔ Drain excess hydraulic fluid if necessary – If leaks were present, check the hydraulic reservoir and prepare to top it off later.
Step 3: Installing the New Cylinder
Installing a new cylinder requires precision and proper alignment to prevent leaks or operational issues. Ensure that all components are securely positioned before finalizing the installation.
✔ Align the cylinder with the lift arms – Ensure that the hydraulic ports are correctly positioned to prevent hose kinks.
✔ Insert new pins, ensuring they are fully secured.
✔ Secure the cylinder before reattaching hydraulic hoses –
* Hand-tighten the hydraulic fittings first to ensure proper alignment.
* Fully secure the fittings afterward using appropriate tools.
✔ Bleeding the hydraulic system – Once all hydraulic lines are connected and the cylinder is installed, the liftgate system must be bled to remove air and ensure proper function:
1. Reconnect the power supply.
2. Loosen the return-to-pump line (not the supply line) on each cylinder, leaving it finger-tight to
allow air to escape.
3. Refill the hydraulic reservoir to the proper level before activating the system.
4. Tap the raise switch gently (for half a second at a time) until hydraulic fluid starts purging
from the loosened fittings. Continue tapping until the fluid flows without air bubbles.
5. Tighten all fittings securely once fluid flows steadily.
6. Recheck the fluid level in the reservoir and refill as needed.
✔ Final system check – Once the hydraulic system is bled and filled, perform a full functionality test:
1. Raise the truck’s lift gate fully and ensure both sides lift evenly.
* If the gate raises unevenly, hold the raise switch for up to 5 seconds in the fully raised
position to force out any remaining air.
2. Cycle through all operations:
* Fully lower the gate.
* Open and raise it.
* Lower it again, then fold and stow it.
3. Inspect for leaks and check the hydraulic fluid level again, refilling if necessary.
Step 4: Final Checks Before Powering On
Before restoring power, it’s essential to verify that everything is installed correctly. Skipping this step could result in malfunctions or hydraulic failures.
✔ Grease the pins – Apply heavy-duty grease to each new pin through its grease fitting to reduce friction and prevent wear.
✔ Inspect hydraulic connections – Ensure hoses, fittings, and seals are tight and free of leaks.
✔ Reconnect power – Reattach the fused power cable to the positive (+) battery terminal.
✔ Test the liftgate without a load – Run a test cycle with no weight to confirm smooth operation.
✔ Check and refill hydraulic fluid – Use the proper hydraulic oil for your liftgate to ensure proper operation.
Finding Liftgate Repair Near Me
If you're unsure about replacing a hydraulic cylinder yourself, it's always best to seek out professional liftgate repair near me to ensure safe and proper installation. Many local truck and trailer repair shops specialize in hydraulic system maintenance, including cylinder replacements. To find a qualified technician, search for authorized lift gate service providers in your area or contact Maxon’s official support team for recommendations.
Conclusion
Replacing a hydraulic cylinder on a Maxon tuck-under liftgate is a critical maintenance task that requires proper safety measures and attention to detail. Replacing the complete cylinder, and not just patching the issue with a cylinder seal kit is a positive investment in both the liftgate and your business to keep you operational. This guide outlines general best practices for replacing hydraulic cylinders on dual-cylinder tuck-under models. These procedures apply to GPT, GPTWR, GPTLR, and select TE models (TE25DC and TE33), as they all utilize a dual-cylinder lifting system.
However, always refer to Maxon’s official service manual for model-specific installation details and consult a qualified technician if you are unsure about any step. Improper installation or maintenance may result in equipment malfunction, injury, or property damage.
By using Maxon-approved replacement liftgate parts, following proper safety protocols, and ensuring the correct installation procedures, you can help maintain your lift gate performance and reduce potential risks.
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