One of the most common debates in the dump trailer industry is whether a scissor hoist or a telescopic cylinder is the better lifting system.
The truth is that both systems work extremely well when properly designed and installed.
At Primary Mover, we offer both scissor hoist kits and telescopic cylinder kits because each system has advantages depending on the application.
The key is understanding the strengths and compromises of each design.
Why Telescopic Cylinders Have Become So Popular
In recent years, telescopic cylinders have gained significant popularity throughout the dump trailer market.
Much of that popularity comes from one major advantage:
Superior lifting geometry.
A telescopic cylinder lifts from the front of the dump body.
If you imagine lifting a couch, you would naturally want to lift it from one end rather than crawling underneath the center and trying to push it upward.
The same principle applies to dump trailers.
Because the telescopic cylinder is positioned near the front of the dump body, it often enjoys a more favorable leverage position throughout much of the lift cycle.
This is one reason telescopic cylinders have earned a reputation as the heavy-lift champions of the dump trailer world.
Why Scissor Hoists Have Been Around So Long
Despite the recent popularity of telescopic cylinders, scissor hoists remain one of the most proven lifting systems ever used on dump trailers and dump trucks.
Scissor hoists have been successfully operating for decades in countless applications.
The design offers several advantages:
- Excellent structural support under the dump body.
- Improved load stability.
- Compact packaging.
- Shorter cylinder requirements.
- Smaller hydraulic oil requirements.
One of the biggest advantages of a scissor hoist is that it can achieve significant lifting performance using a relatively short cylinder stroke.
The mechanical advantage created by the scissor mechanism allows a smaller cylinder to perform work that would otherwise require a much longer direct-acting cylinder.
Why Scissor Hoists Became So Popular Originally
In the early days of electric hydraulic systems, flow rates were much lower than they are today.
Many dump trailers relied on relatively small hydraulic power units.
Because telescopic cylinders require substantially more hydraulic oil volume, dump cycles were often very slow.
Scissor hoists became extremely popular because they could achieve good lifting performance while requiring much less cylinder volume.
The result was faster dump cycles using smaller hydraulic systems.
Modern Telescopic Systems Have Improved Dramatically
Today's telescopic systems are much better than the systems of the past.
Shorter four-stage telescopic cylinders have become increasingly popular.
High-performance hydraulic power units have also improved dramatically.
At Primary Mover, our telescopic cylinder systems utilize high-flow hydraulic power units designed to improve dump speed and overall performance.
The gap between telescopic and scissor hoist dump speeds is much smaller today than it was years ago.
The Biggest Advantage of a Telescopic Cylinder
The biggest advantage is simple:
Lifting geometry.
Because the cylinder acts directly on the dump body near the front of the bed, less reliance is placed on M-value calculations, linkage geometry, and scissor placement.
This often makes telescopic systems more forgiving when it comes to installation design.
That does not mean geometry becomes unimportant.
It simply means there are fewer variables involved.
The Biggest Advantage of a Scissor Hoist
The biggest advantage of a scissor hoist is efficiency.
A properly designed scissor hoist can:
- Use a smaller cylinder.
- Use less hydraulic oil.
- Require a smaller reservoir.
- Provide excellent stability.
- Offer outstanding lifting performance.
When all of the system components are properly matched, a scissor hoist can be extremely effective.
The challenge is that the entire system must work together.
The Importance of Synergy in a Scissor Hoist
One word we often use when discussing scissor hoists is synergy.
Every component must work together properly.
That includes:
- M-value
- Rear overhang
- Dump angle
- Hydraulic pressure
- Hydraulic flow
- Stroke length
- Hoist placement
If one of these factors is poorly matched, the overall performance of the hoist suffers.
This is one reason some people mistakenly believe scissor hoists cannot lift as much as telescopic cylinders.
In many cases, the problem is not the hoist itself.
The system simply was not optimized.
Reservoir Size Differences
One major difference between the two systems is hydraulic oil volume.
A telescopic cylinder is typically a single-acting design.
When the cylinder extends, all of the hydraulic oil required for that extension must leave the reservoir and enter the cylinder.
When the cylinder retracts, all of that oil must return to the reservoir.
This requires a significantly larger hydraulic tank.
Scissor hoists often utilize double-acting cylinders.
Because oil exists on both sides of the piston, the cylinder itself effectively acts as part of the hydraulic system's oil storage capacity.
As a result, scissor hoists generally require much smaller reservoirs.
Maintenance and Serviceability
Every hydraulic component will eventually require maintenance.
The question is how that maintenance is performed.
Telescopic cylinders contain:
- Multiple stages
- Multiple seals
- Multiple wear surfaces
While modern telescopic cylinders are extremely reliable, additional stages create additional components that can eventually require service.
Scissor hoists use a simpler cylinder arrangement.
The cylinder is often easier to understand and troubleshoot.
If a repair is ever needed, the cylinder can typically be serviced or replaced without replacing the entire hoist structure.
Loading Equipment Damage
Older telescopic cylinder designs often extended significantly above the dump body when fully retracted.
This created situations where excavators, loaders, and other equipment could accidentally strike the cylinder during loading.
Modern four-stage telescopic cylinders have significantly reduced this issue by lowering overall retracted height.
While not completely eliminated, it is much less common than it once was.
Which System Lifts More Weight?
There is no universal answer.
A properly designed telescopic system can lift tremendous loads.
A properly designed scissor hoist can also lift tremendous loads.
The real question is whether the system was properly designed for the application.
The best-performing dump systems are not determined by whether they use a scissor hoist or telescopic cylinder.
They are determined by whether all components work together correctly.
Which System Does Primary Mover Prefer?
The answer is simple:
We like both.
Both systems have strengths.
Both systems have tradeoffs.
Both systems can provide years of reliable service when properly selected and installed.
For some applications, a telescopic cylinder may be the better choice.
For others, a properly designed scissor hoist may provide better value, better packaging, and excellent performance.
That is why we offer both options and help customers determine which solution best fits their needs.
Final Thoughts
The scissor hoist versus telescopic cylinder debate often focuses on which system is stronger.
In reality, the better question is:
Which system is better suited for your specific application?
If properly designed, both systems can deliver outstanding performance.
The key is understanding the tradeoffs and selecting the right system for your dump trailer, dump truck, or commercial hauling operation.
Need help deciding between a scissor hoist and a telescopic cylinder? Call Primary Mover at 985-888-6554.
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