Skip to content

Implements Direct Implements Direct

How to choose a PTO Post Hole Borer for your Tractor

Choosing the best PTO (Power Take-Off) powered post hole digger for your tractor can significantly increase your efficiency with projects like fence building, landscaping and tree planting. Here's a comprehensive guide from Implements Direct  to help you make an informed decision:

Tractor with post hole digger


Assess Your Needs:

  •  Type of Soil: Consider the soil type you'll primarily be working with (e.g., sandy, clay, rocky) as this will affect the power and capabilities required from the post hole digger.
  • Depth and Diameter Requirements: Determine the typical depth and diameter of holes you need to dig. This will help you choose an appropriate auger size . Commonly for Fencing it maybe a 9" or 12" auger and maybe even larger if you have very big strainer posts. For tree planting it could be 12" or larger depending on the tree size.  All of the post hole borer augers can dig down to about 1.2m deep. This is limited by the tractor being able to extract the auger out of the hole and above the ground again so you can travel around . For this reason PTO post hole borers done use  auger extensions because the tractor does not have enough uplift to get the extended auger clear of the ground.
  • Tractor Compatibility: Ensure compatibility with your tractor's PTO horsepower and 3 point hitch specifications. Refer to your tractor's manual for its PTO horsepower rating. And check out our article covering tractor linkages and how to identify the category of  3 point  hitch that you have.

Types of Post Hole Diggers:

1. Standard Duty: Suitable for compact and sub compact tractors for lighter-duty tasks. Ideal for smaller-scale projects like lifestyle block fencing and tree planting. This model suit category one linkage and tractors generally upto 30- 40 HP. And Augers sizes up to 12"


Small tractor with post hole digger
2. Medium Duty: This larger model offers a balance between power and affordability. Suitable for regular use in various soil types and can be adapted to use on tractors with category 1 or  category 2 3 linkage , This post hole digger can be fitted with  augers from 6"- 24" inch. It has holes for category 1 or 2 linkage pins for the lower arms and has a category 1 19mm hole for  where it attaches to the tractors top link mounting point. 
PTO Post Hole Borer Large (No Auger)

3. Heavy Duty: Designed for intensive use, capable of handling tough soil conditions, rocky or hard sedimentary soils with its hydraulically assisted down force. Ideal for digging  larger  diameter holes in tougher conditions. This unit is supplied with category 2 lower linkage pins and category 2, (25mm) hole for mounting to the top link clevis on your tractor.  It can run a 6"-24" diameter auger.


Hydraulic down force post hole digger

 Features to Look For:

  • Auger Size: Choose the auger diameter based on your post size requirements. Common sizes for fencing are  from 9 to 15 inches. Common drive type and size  for PTO driven post hole augers is 50mm diameter round shaft  this is where the auger connects to the gearbox. This is a different standard from augers used on hydraulic excavator  drives etc.9" Auger
  • Gearbox and Transmission: Opt for models with robust gearboxes with some protection to the transmission systems to handle high torque loads that might occur if you find some buried object ie tree roots or rock, this will  ensure longevity.All the Sierra post hole borers have a PTO shaft with a Shearbolt coupling which will protect the gearbox and tractor driveline from shock loads.  The Shear Bolt will break and instantly unload the stress from the driveline. It's easy to replace and requires minimal maintenance and superior reliablity compared with a slip clutch. 
  • Adjustable Depth Control:Look for models with adjustable depth control mechanisms so it can be adjusted for your tractors height and geometry.
  • Safety Features: When selecting the best post hole borer look at what safety features such as shear bolts or clutches , protective shields on rotating parts that are fitted.
  • Ease of Maintenance: Select models with easily accessible components for maintenance and repairs. The Sierra models have an Oil filled gearbox which requires minimal maintenance and  standard PTO driveline fittings with grease points on the universals , without a slip clutch to have to unfreeze and maintain  the shear bolt system requires minimal maintenance and is the preferred choice for this sort of implement.
  • Compatibility with Accessories: Some post hole diggers use different size linkage pins, it's important to choose the right one thats going to fit your tractor. There are also different size augers in the market which can be fitted to different types of post hole diggers , The standard drive size and type for PTO powered post hole borers is 50mm round , so the auger needs to have a 50mm diameter round socket to fit to the post hole borer gearbox. You also want to check that spare parts are available should you need it like auger teeth or shear bolts.  Many of these parts are standard and can be sourced from many agricultural  implement suppliers, Implements direct New Zealand has the wear parts for these augers in our parts section here

By following these steps and considerations, you can select the best PTO powered post hole digger for your tractor, ensuring efficient and effective hole digging for your projects.