What Is High Flow on a Skid Steer? (Explained & When You Need It)

The High-Flow Bottom Line

This guide breaks down exactly what high-flow hydraulics are, why this feature is critical for certain jobs, and how to decide if it’s the right investment for you. We’ll give you a clear framework for making a smart decision that boosts your productivity and protects your bottom line.

• What It Is: High-flow is a premium hydraulic system that pumps fluid much faster (measured in Gallons Per Minute or GPM) than a standard system. Think of it as a pressure washer with a much bigger engine—it delivers significantly more power to run demanding attachments.
• When You Need It: You absolutely need high-flow for power-hungry attachments like forestry mulchers, cold planers (asphalt grinders), and rock saws. For general tasks that define what a skid steer is used for, like moving pallets, digging with a bucket, or sweeping, standard-flow is all you need.
• Is It Worth It? If your work depends on high-power attachments, high-flow is a non-negotiable investment for productivity. A high-flow machine can also operate in standard-flow mode, making it more versatile than a standard-flow-only machine.
• How to Check: The easiest way to tell if a skid steer has high-flow is to look inside the cab for a specific button or switch that activates the system, often marked with a unique symbol.

Stage 1: Defining the Flow: What Are We Talking About?

To make a confident decision, you first need to understand the basic principles at play. This section demystifies the core concepts of hydraulic flow, giving you a solid foundation for everything that follows.

Hydraulic flow is the movement of pressurized fluid that acts as the lifeblood of your skid steer, powering its lift arms and attachments. The key difference between machines lies in how much power their hydraulic system can deliver.

• Standard-Flow vs. High-Flow: A simple comparison of the two system types.

• Standard-Flow: This is the baseline hydraulic system found on all skid steers. It’s designed for general-purpose tasks and a wide range of common attachments.
• High-Flow: This is an optional, upgraded system that provides significantly more hydraulic power. It’s engineered specifically to run high-performance attachments that require constant, high-speed movement.

• Key Metrics You Need to Know:

• Flow Rate (GPM): This measures the speed at which hydraulic fluid moves, expressed in Gallons Per Minute. High-flow systems have a much higher GPM, allowing them to spin attachment motors much faster.
• Hydraulic Horsepower (HP): This is the true measure of an attachment’s potential power. It’s a crucial metric calculated from both the system’s flow rate (GPM) and its pressure (PSI).

Stage 2: The Stakes: Why This Decision Matters for Your Bottom Line

Choosing between a standard-flow and high-flow system is a major financial decision with long-term consequences for your operational efficiency and profitability. This choice directly impacts your initial investment, your running costs, and the types of jobs you can take on.

• The High-Flow Advantage:

• Increased Power & Productivity: The primary benefit is the ability to run more powerful attachments and complete demanding jobs in a fraction of the time. More power means more work done per hour.
• Greater Versatility: A high-flow machine can do everything a standard-flow machine can, but not the other way around. This flexibility allows you to bid on a wider range of projects.

• The High-Flow Trade-Offs:

• Higher Initial Cost: Expect to pay 15-25% more for a skid steer equipped with a factory high-flow system.
• More Expensive Attachments: High-flow attachments are built to handle more stress and can cost 30-50% more than their standard-flow counterparts.
• Increased Operating Costs: Pumping more fluid requires more engine power, leading to higher fuel consumption and more complex maintenance needs over the life of the machine.

• The Case for Standard-Flow:

• Lower Cost of Entry: If your work doesn’t require extreme-duty attachments, a standard-flow machine offers a significantly lower initial investment for both the machine and its tools.
• Simpler & More Efficient: For standard tasks, these systems use less fuel and have simpler maintenance requirements, resulting in lower overall operating costs.
• The Major Limitation: A standard-flow system is incapable of powering the most demanding attachments, which can severely limit your scope of work and potential revenue streams.

Stage 3: The Mechanics: How High-Flow Delivers More Power

Understanding how a high-flow system generates superior power helps clarify why it’s necessary for certain attachments. It all comes down to the engineering differences that translate into real-world performance gains.

A skid steer’s engine drives hydraulic pumps, which send pressurized fluid through hoses to power the attachment’s motor. A high-flow system uses larger pumps and reinforced components to move a much greater volume of that fluid at high pressure, generating significantly more hydraulic horsepower.

• The Numbers Game: Comparing System Outputs:

• Standard-Flow Range: These systems typically operate in the 15-26 GPM range at a pressure of around 3,000 PSI.
• High-Flow Range: These systems push the volume up to 25-45 GPM, providing up to twice the hydraulic power of a standard system to keep demanding attachments running at peak speed.

• Calculating True Power (Hydraulic Horsepower):

• The Formula: You can calculate any system’s power using this simple formula: (PSI x GPM) / 1,714 = Hydraulic HP.
• Real-World Example: A strong standard-flow system might produce (3,336 PSI x 26 GPM) / 1,714, which equals 50.6 HP available to the attachment.

• Physical Differences in a High-Flow System: A true high-flow machine isn’t just a bigger pump. It includes a suite of heavy-duty components like larger hydraulic pumps, additional oil coolers to manage heat, reinforced lines and couplers, and larger fluid reservoirs.

Stage 4: The Breakdown: Matching Attachments to Hydraulic Flow

This is where the decision becomes crystal clear: the attachments you plan to use are the single most important factor in determining your hydraulic needs. Mismatching an attachment to your machine’s flow rate will lead to poor performance, frustration, and potential damage.

• Category 1: High-Flow Required: These high flow skid steer attachments have large hydraulic motors designed for continuous, high-speed operation. They will stall, underperform, or fail to run altogether on a standard-flow system.

• Examples: Cold Planers, Forestry & Disc Mulchers, Rock Saws, Stump Grinders.

• Category 2: High-Flow Recommended: These attachments can run on standard-flow, but their performance and efficiency increase dramatically with a high-flow system. When you are clearing land with your skid steer, a high-flow brush cutter or trencher will complete the job much faster.

• Examples: Augers, Brush Cutters, Snow Blowers, Trenchers, Power Rakes.

• Category 3: Standard-Flow Sufficient: These attachments are designed for standard-flow systems and gain no benefit from high-flow. Their function is based on hydraulic pressure and cylinder movement, not high-speed motor rotation.

• Examples: Standard Buckets, Pallet Forks, Grapples (learn what a grapple bucket is), Sweepers, Snow Pushers.

Stage 5: The Action Plan: Your High-Flow Decision Framework

Instead of guessing, use this systematic approach to determine your exact needs and make an informed investment. This simple three-step method removes uncertainty and empowers you to choose the right machine for your work.

The A.V.C. Method: Assess, Verify, Calculate

• Step 1: ASSESS Your Workload & Attachments

• Analyze the primary jobs you will perform 80% of the time. Are they heavy-duty applications like mulching, milling asphalt, and grinding stumps? Or are they general tasks like lifting, loading, and grading? Your attachments dictate your hydraulic needs.

• Step 2: VERIFY the Machine’s Capability

• In the Cab: The most reliable method is to look for a dedicated high-flow activation switch, button, or setting on the machine’s control panel.
• On the Spec Plate: Locate the machine’s specification plate (usually in the cab or on the frame) and find its rated hydraulic flow in GPM.
• With the Seller: When in doubt, provide the machine’s serial number to a dealer or the manufacturer to confirm its factory specifications.

• Step 3: CALCULATE the Total Cost of Ownership

• Don’t just look at the sticker price. Factor in the higher initial price of the machine, the premium for high-flow attachments, and the potential for increased fuel and maintenance costs. Weigh this against the projected increase in productivity, job speed, and revenue from being able to take on more demanding work.

• Operating a High-Flow System:

• Activating and deactivating the high-flow circuit is typically done via a switch in the cab. Always consult the operator’s manual for the specific procedure for your machine.
• Many modern skid steers can automatically detect the type of attachment connected and adjust the hydraulic flow accordingly, simplifying operation and protecting your tools.

Stage 6: Avoiding Costly Mistakes: Common High-Flow Pitfalls

Making the wrong choice or improperly operating a high-flow system can lead to expensive repairs and significant downtime. Understanding these common pitfalls is essential for protecting your investment.

• The Mismatch Problem: The most common mistake is trying to run a high-flow attachment on a standard-flow machine. This will result in severe underperformance, constant stalling of the attachment, and can strain the machine’s hydraulic system, leading to premature wear or damage.
• The “Can I Just Add It Later?” Question:

• While aftermarket kits to add high-flow exist, they are expensive, complex to install, and may not provide the same level of performance or cooling as a factory system.
• Critically, installing a third-party hydraulic kit will almost certainly void your machine’s warranty.
• It is almost always more reliable and cost-effective to buy a machine that was built with a high-flow system from the factory.

• The Overheating Risk: High-flow systems generate immense heat, which is the enemy of any hydraulic system. Be aware of common issues like hydraulic leaks, clogged filters, and overheating. These systems demand diligent maintenance to keep them running cool and efficiently.

Stage 7: The Transformation: From Operator to Strategic Owner

Ultimately, understanding high-flow hydraulics is about more than just technical specifications; it’s about making a strategic business decision. Choosing the right system transforms you from a simple operator into a strategic owner who can maximize versatility, efficiency, and return on investment.

• The Power of Versatility: A high-flow skid steer is effectively a two-in-one machine. It can be switched into standard-flow mode to perform everyday tasks with maximum fuel efficiency, then switched back to high-flow to tackle specialty jobs that others can’t, maximizing its utility and earning potential.
• Connecting Flow to Machine Size: High-flow systems are most common on larger skid steers, typically those with a rated operating capacity (ROC) over 1,700 lbs. This is because the machine’s larger frame, more powerful engine, and robust cooling capacity are all necessary to handle the immense power and heat generated by the system.
• The Responsibility of Power: Owning a high-flow system is a commitment. It means dedicating yourself to a more rigorous maintenance schedule—checking fluid levels, inspecting coolers, and replacing filters—to protect your powerful investment and ensure it delivers peak performance for years to come.

Frequently Asked Questions

What is high-flow on a skid steer?

High-flow is an upgraded hydraulic system that pumps fluid at a much higher rate (Gallons Per Minute or GPM) than a standard system. This increased flow generates significantly more hydraulic horsepower, which is essential for running demanding, high-performance attachments.

When is a high-flow system absolutely necessary?

You absolutely need a high-flow system for attachments with large hydraulic motors designed for continuous, high-speed operation. This includes tools like forestry mulchers, cold planers, rock saws, and large stump grinders, which will stall or fail to run on a standard-flow machine.

How can I tell if my skid steer has high-flow?

The most reliable way is to look inside the cab for a specific button, switch, or digital control that activates the high-flow circuit. You can also check the machine’s specification plate for its GPM rating or provide the serial number to a dealer to confirm its factory configuration.

Is a high-flow skid steer worth the extra cost?

If your work depends on high-power attachments like mulchers or cold planers, high-flow is a non-negotiable investment for productivity. A high-flow machine can also operate in standard-flow mode, making it more versatile and increasing its potential revenue streams.

Can I run a standard-flow attachment on a high-flow machine?

Yes. A high-flow skid steer is a versatile, two-in-one machine that can be switched into standard-flow mode. This allows you to operate standard attachments like buckets and grapples with optimal fuel efficiency, protecting the attachment from excessive flow.

Is it worth adding a high-flow kit to a standard machine later?

It is generally not recommended. Aftermarket high-flow kits are expensive, complex to install, and may not provide the same cooling capacity as a factory system. Most importantly, installing a third-party kit will almost certainly void your machine’s warranty.

Why does a high-flow system require more maintenance?

A high-flow system generates more power, pressure, and heat, which puts additional strain on all hydraulic components, including pumps, motors, hoses, and valves. This requires a more rigorous maintenance schedule for checking fluid, inspecting coolers, and replacing filters to prevent overheating and premature wear.

What is the typical GPM range for high-flow vs. standard-flow?

Standard-flow systems typically operate in the 15-26 GPM (Gallons Per Minute) range at around 3,000 PSI. High-flow systems significantly increase this volume, operating between 25-45 GPM to deliver the power needed for demanding attachments.