This is the most important compatibility question in the attachment world — more important than quick-attach compatibility, more important than brand. If you run a high-flow attachment on a standard-flow machine (or vice versa), you will either get poor performance or damage your equipment. Here's the complete guide.
Hydraulic attachments — augers, mulchers, snow blowers, trenchers, stump grinders, brooms, anything with a spinning or moving hydraulic motor — require a minimum volume of hydraulic oil (GPM) to operate correctly. Your skid steer provides either standard flow or high flow hydraulic output through its auxiliary circuit.
High-flow attachment on a standard-flow machine: The attachment will run — but slowly, weakly, and under spec. A mulcher designed for 30 GPM running on 18 GPM won't cut properly, will bog down on any real material, and you'll be pushing a very expensive paperweight around the field. Warranty on the attachment is often void for this damage.
Standard-flow attachment on a high-flow machine: This is less catastrophic but still a problem. Too much flow through a motor designed for lower GPM can cause overheating, overspeed damage, and seal failure. Many standard-flow attachments have flow limiters built in. Some don't. Check before you connect.
Check your skid steer's spec sheet or operator's manual under "auxiliary hydraulic flow" or "high flow auxiliary hydraulic flow." Common values by machine size:
| Machine Class | Typical Std Flow (GPM) | High Flow Available? |
|---|---|---|
| Mini skid steer (under 2,000 lbs) | 8–12 GPM | Usually no |
| Compact skid steer (2,000–5,000 lbs) | 14–18 GPM | Some models with option |
| Mid-frame skid steer (5,000–7,500 lbs) | 17–22 GPM | Optional on most brands |
| Large skid steer / CTL (7,500+ lbs) | 20–24 GPM std / 34–45 GPM HF | Yes — separate high-flow circuit |
| Bobcat S770 / T870 class | 26 GPM std / 40 GPM HF | Yes |
| John Deere 333G / 333P class | 21.5 GPM std / 39 GPM HF | Yes |
| Kubota SVL97-2 | 25 GPM std / 38 GPM HF | Yes |
Many manufacturers offer the same attachment in standard-flow and high-flow variants. Baumalight, HLA, Blue Diamond, and Virnig all make this distinction explicitly. When you see "HF" or "High Flow" in a model name (like Baumalight MP272 HF or TMG SFM72 HF), that's telling you this model requires high-flow auxiliary.
High flow (GPM) is about volume. Pressure (PSI) is separate. Most attachments run at 3,000–3,500 PSI system pressure — standard across virtually all modern skid steers. You're almost never mismatched on pressure. The mismatch problem is almost always volume (GPM).
Find your machine's auxiliary hydraulic flow spec. Look at the attachment's required GPM. If the attachment requires more than your machine produces, either upgrade the machine's flow option or buy the standard-flow version of the attachment.
For most Canadian operators running mid-frame machines without high-flow, stick to standard-flow tools. If you're buying a mulcher or large snow blower, verify your machine's spec first — this is the one compatibility check that will save you an expensive repair bill.