John Shearer Mk4 Universal precision seeding bars works out to 18.3m (60ft)

Shearer engineers have introduced a design update for the Mk4 seeder bar that incorporates an advanced hydraulic control system and have added Active-Pack

The John Shearer Mk4 precision seeder bar introduces the most current tine opener technology and Active Pack packing pressure system for the first time in model configuration options from single to dual fold with working width from 9.8 to 18.3m (32 to 60ft)

John Shearer has released the most versatile purpose-built seeding bars ever offered with double fold models sowing across 15.2 to 18.3m (50 to 60ft) while single fold widths range from 9.8 to 12.2m (32 to 40ft)

John Shearer’s Mk4 Universal seeder bar has reached a pinnacle in direct drill design that builds on a lineage of robust and effective Shearer seeding models with all the improvements needed to meet current grower expectations.

John Shearer has been providing local growers with farm equipment since 1877.

Always with a proud locally made and design factor that ensured high-quality models able to handle the tough ground that growers had to endure.

And while the most successful models from this pioneering firm and recent emphasis have been toward their range of direct drills for medium size farm operations planting specialist crops or rejuvenating pasture, there has always been a stalwart and loyal group of growers making full use of the John Shearer broadacre seeder bar.

And with the success of the AP6 direct drill to a level where virtually no more improvements were needed, Shearer engineers have been busy perfecting their broadacre seeder bar to a level where it can equal and even better some highly fancied imported models, with its home ground advantage.

Shearers have always built to suit our local conditions, and this latest machine – the Mk4 seeder bar – is no exception.

Shearer engineers don’t intend to hold back on talking about their experience and expertise that has gone into this heavy-duty Mk4 seeder bar, and how they expect this model to set a benchmark as it tops the market offerings.

The John Shearer Mk4 Universal seeder bar is fitted with wider wheels and tyres for improved ground floatation in soft soil and with tine breakout pressure increased to 590kg while working across four sowing ranks for ultimate placement

Mk4 seeder bar build

John Shearer engineers immediately point to the unique combination of Shearer’s robust equipment structure build that is complemented with a completely new hydraulic tine opener assembly to ensure the most accurate placement.

And the unique linkage design that ensures the entire assembly retains the same working angle as it follows any changes in the ground contour.

Part of the upgrades include adding wider wheels and tyres into the design with the aim to ensure better floatation in soft soil and with a maximum front tine breakout pressure of 620kg when the seeder bar needs to handle tougher soils.

Keeping with a Shearer tradition build that has preceded the Mk4, the four-row universal seeder bar incorporates the design and build for maximum structural strength and long service life.

 Tine and press wheel configurations include the choice of 32 to 73 precision tine openers set in 255mm (10-inch) or 305mm (12-inch) spacings on four sowing ranks

The main frame includes four rows of 100mm x 100mm mounting ranks, of which the front and rear centre section beams are 9mm thick steel tubes.

Both single-fold, with narrow and standard centre sections, and double-fold models (standard centre only) versions are available, with both variants able to fold to 7.8m wide for road transport.

Working widths for the wide ground covering six double-fold models are, 15.2, 17.1 and 18.3m (50, 56, and 60ft) while growers with medium size operations may opt for one of the four models in the single-fold range that offers sowing widths from 9.8 to 12.2m (32 to 40ft).

Depending on the model, there are from 32 to 73 precision tine openers that can be set in 255 or 305mm (10 or 12-inch) spacings on the four sowing ranks. There is an 800mm underframe clearance.

Design updates

Behind the success of the current John Shearer operation is the well respected operations manager Franco Perrotta.

Buyers are unanimous when it comes to extolling the virtues and the lengths that Franco has gone to first ensure their model purchase best suits the intended operation, and then having any initial set-up issues sorted out quickly.

And John Shearer’s operations manager Franco Perrotta will be another factor in making sure the Mk4 universal seeder bar settles into working operation quickly, and had this to say, “The Mk4 seeder bar is like no other machine on the market.

“The most notable improvement on the Mk4 seeder bar is the current design, precision tine opener. Wielding an impressive 620kg of breakout force, the opener has been designed to work in every terrain it will encounter in our local conditions, and that includes working through heavy ground,” Franco added.

The John Shearer Mk4 seeder bar has been built to suit our local conditions and Shearer engineers have placed the conviction of all their experience and expertise to build this heavy-duty seeder bar to set a benchmark for the most current market offering

Nothing is left to chance within this Mk4 seeder bar design as the process begins with the opening tine cultivating deeply to help roots seek out moisture and increase water infiltration.

Then fertiliser is banded deeply into the open furrow and covered by a closer plate that creates a unique seed bed to prevent seed to fertiliser contact, with the notion of reducing the chance of toxicity.

As the process continues the seed tube then places the seed above the fertiliser, on the seed bed created with the seeding tine/tube regulated independently to achieve the desired seed depth setting required in a range from 6 to 70mm.

The press wheel then does its job by closing the furrow and as a result, creates seed-to-soil contact along with a small rainfall catchment trench.

This is all achieved with the assistance of a parallelogram linkage that is designed to allow the whole unit to move up and down while following ground contours while remaining at the same seeding angle.

The main hydraulic ram provides the regulated force required for the tine opener to break into the ground through normal operation and also has the ability to breakout effectively if an obstacle is encountered.

The press wheel hydraulic ram is designed to use the independent pressure from the main ram to supply constant pressure as it operates through the soil, and also enable the operator to change packing pressure on the go as the seeding shank and press wheel swivel up to 30-deg either side.

Shearer engineers have gone a step further with the Mk4 seeder bar. In conjunction with the advanced hydraulic control system, they have also added Active-Pack. This allows the operator to change the required packing pressure on the press wheel as required.

Active-Pack works to maintain the desired pressure constantly by varying the hydraulic pressure on the press wheel ram as conditions change across the paddock, ensuring smooth movement regardless of potential terrain extremities.

Find out why growers are switching to this latest release Mk4 seeder bar with Active-Pack technology at or contact for your nearest dealer on tel: 08 8468 4190 or email:

Precision tine openers

John Shearer engineers have taken their tine opener technology to new heights with the release of the Mk4 precision seeder bar.

The technology applied behind the precision tine openers with swivelling press wheels places this four-row Mk4 precision seeder bar at the forefront of seed placement adjustable to multiple depths with a front tine break-out of 590kg.

And includes what John Shearer engineers term as Active Pack that takes full advantage of the packing pressure that can be applied. In this instance, it makes sure the seed in the furrow is correctly packed and closed to avoid any erosion risk while maintaining moisture.

And is smart enough to draw any ground moisture up toward the seed by pressing out any blocking sods in between.

Once the operator has set the packing pressure on the press wheel Active Pack will then take over and maintain the pressure constantly as conditions change across the paddock.

And so well thought out is this model that this tine technology has the ability to suit just about every planting situation with configuration options from single to dual fold with working width from 9.8 to 18.3m (32 to 60ft).

Learn more about the latest John Shearer tine technology at or contact your nearest dealer on tel: 08 8468 4190 or email:

John Shearer Mk4 Universal seeder bar specs