If you’ve ever drilled post or utility holes with a skid steer, you’ve probably wondered how far you can really go before the auger maxes out. The short answer: it depends on your setup. We know, boring and vague (but true!) answer.
We make attachments, though, so we may as well use our own as a more specific example. With a Prime Attachments Earth Auger, you’re looking at about 48 inches deep with a standard bit, and up to 72 inches or more with an extension. That’s deep enough for most fence posts, sign bases, footing holes, and even telephone poles (a standard 40-foot pole is buried 6 feet deep). It’s also easily deep enough to plant shrubs or young trees.
The beauty of doing your augering with a skid steer is that you don’t even need to swap machines or call in an excavator. Let’s “dig” into the details.
Most skid steer auger attachments use a 4-foot (48") auger bit as standard. You won’t see many sold in lengths much greater because 4 feet is plenty for skid-steer appropriate digging tasks like typical Midwest frost lines, post holes, and foundation prep. That rule of thumb is what guided the heavy-duty design of the Prime Attachments auger, which handles that depth with power to spare.
But when you need to go deeper — say, for deep drainage systems, big commercial footing piles, or those telephone poles we mentioned — our 24-inch extensions give you the reach without sacrificing stability. Oh, and if you’re drilling deep, remember that the longer the auger, the more torque your machine will need to stay efficient. Our planetary gearbox direct drive setup delivers that torque to keep rotation steady and clean, even in dense soil.
Even with the right length auger bit, real-world digging depth depends on a few key factors:
In other words, bit length is just part of the picture. Torque is the real limiter. It takes a high-torque auger skid steer attachment equipped for 3,000 PSI to handle 6-foot drilling depth and 2-foot width with standard extensions and no loss of rotation speed.
For straight vertical holes like posts, piers, ball-rooted trees, or fence lines, an auger for skid steers wins every time. It’s fast, it’s precise, and the smaller vehicle minimizes surface disruption.
With that said, if your skid steer project calls for trenching, running utility lines, or deep, wide-footed holes, a backhoe attachment will likely give more control and efficiency at deeper angles. Augers dig clean, narrow holes; backhoes move bulk earth. Feel free to compare them, but for most contractors, having both means you can cover 95% of excavation jobs with one skid steer and two attachments.
Going deep is one thing. Staying straight is another. Here’s a few field-tested habits that can help:
These best practices set you up to succeed. Still, we do everything we can to help you out with a heavy-duty post hole auger design, too. Our Earth Auger attachment features a 2" hex drive for stability and greasable pivot points to keep it centered and durable during repeated use. Add the self-centering frame, and you’ll notice cleaner starts and straighter holes every time.
So…how deep can a skid steer auger really dig?
About four feet standard, six feet with extensions, and as deep as your torque and soil will let you.
Luckily, that’s the perfect range for contractors like fence builders and sign installers. Even if you mainly handle high-volume commercial jobs or challenging tasks like drilling through compacted fill or frost, a heavy-duty post hole auger setup gets it done. The added gearbox torque and reinforced frame of the Prime Earth Auger reduces your flex and vibration, so you get smoother operation even when ground conditions are nasty. You’re drilling clean, straight, and strong.
When you’re ready to see what your skid steer can really do, request a quote or check out the full lineup of attachments that take your machine from good to downright badass!