It's a considered purchase in a crowded market. Kondinin Group's January 2025 chaser bin research report counted around 40 manufacturers and importers supplying Australia, and put a typical 30 to 40 tonne bin in the multiple 6 figures price category. At that money, the right questions matter more than the brochure, so we've organised this guide around the same checkpoints Kondinin's researchers inspect when they put chaser bins through their paces.
Factors to consider when choosing a chaser bin:
(Get the first two right and most of the rest falls into place.)
- How much capacity you need
- Axle configuration (single or dual axle)
- The auger system
- Build quality
- Running gear
- Which options are worth paying for
- Ease of maintenance
- Transport logistics
- After-sales support from the manufacturer
1. How much capacity do you need?
Chaser bin size
We've covered what size chaser bin you need in more detail, however as a general working rule, your chaser bin should hold at least two full header grain tanks, and three is more comfortable. Most single-header operations land between 25 and 35 tonnes; multi-header operations and long paddock-to-truck runs justify 35 to 45 tonnes.
Make sure to compare capacity volumetrically, not by the badge as grain weights and density differ per crop and species. The tonnage on the decal is often a wheat rating only, so two '30T' bins from different brands can hold different volumes; Kondinin's researchers rate capacity the most important consideration and recommend comparing bins in litres or cubic metres, not just chasing the largest model number; a bin never carries its wheat rating in canola or oats. Davimac publishes both figures for every model.
2. Single-Axle or Dual-Axle?
Axles
When comparing single axle vs dual axle chaser bins, it's important to understand they serve different purposes and impact the soil in different ways. Single axle bins are lighter, simpler and cheaper, and suit 25 to 30 tonne capacities or where maneuverability is paramount. Dual axle bins spread the load across four tyres on a walking beam undercarriage, which means less compaction, smoother towing over rough ground, and larger capacity up to 45 tonnes.
Kondinin's report observes that nearly every bin over 30 tonnes runs a tandem or triple axle, that walking beam configurations are popular for keeping tyres in ground contact through rough country, and that steerable axles earn their place through tighter turning and less scuffing. The Davimac 45T runs a self-steering rear axle as standard.
Also ask what the undercarriage was designed for: purpose-built paddock running gear, or road axles adapted with spring packs and shackles that become wearing parts.
3. The Auger System
Outload auger
Look for a hydraulically adjustable spout and discharge angle, and a shut-off door to manage flow, all of which are standard on Davimac bins.
Auger diameter
The discharge auger diameter plays a huge role in determining your unload speed. A Davimac 20 inch auger unloads up to 12 tonnes a minute; the 24 inch auger on the 45T up to 18 tonnes a minute, which is a tonne every 3.3 seconds. A bin should empty into the truck comfortably before the header tank fills again. Speed cuts both ways, though; at a tonne every few seconds, spout control is what stands between a fast unload and grain on the ground.
Flight thickness
Flight thickness matters more than it looks like it should. Thin flights bow under load over time, and a bowed flight runs out of balance, which shows up as vibration, uneven wear, and a shorter working life. The industry standard is 6 mm flights; Davimac's vertical auger runs 10 mm flights welded around a 150 mm centre pipe specifically to resist that bowing and stay balanced. Whatever brand you're comparing, ask for the flight thickness in writing rather than taking 'heavy duty' as the answer.
Discharge height and side
Check discharge height against your tallest truck or mother bin (Davimac discharge heights adjust between roughly 4.2 and 4.7 metres depending on model and tyres), and discharge side: left-hand is standard, right-hand is a factory option, and changing your mind later is expensive. A long-reach auger option adds 500 mm for high-sided trucks on 25T to 35T models.
Cross auger
The horizontal cross auger that feeds the outload auger is where farmers see the most design variance between brands, and the most operating problems. Check these points:
- How do the cross and vertical augers couple (Davimac runs a direct drive coupling)
- What is the thickness of the flights?
- Whether any centre bearing is sealed or greasable from outside the bin rather than buried in it.
PTO shafts and hydraulic drive
Davimac bins run standard PTO drive at 1,000 rpm with the front PTO shaft included. If your tractor has no PTO, an optional 500 rpm hydraulic drive motor maximises compatibility with older machines, with the trade-offs of a slower unload and a high-flow remote requirement. Whatever the brand, confirm drive speed against your tractor before signing.
Hydraulic connections
Small detail, daily annoyance. Hoses should be clearly labelled, routed along the chassis away from snag points, and have somewhere to live when unhooked so couplings stay out of the dirt. Check none of the routing interferes with cleanout doors or the jack stand, and count your remotes: three minimum for a Davimac, four for the 45T, plus extras for hydraulic options.
4. Body and Build Quality
Weld quality
Kondinin's researchers treat poor welds as an early warning that the whole build may not be up to scratch, and it's a fair test because welds are one of the few build elements you can inspect in the yard. Look along the seams: consistent, clean runs with no undercutting or porosity. Davimac chassis are fully welded rather than bolted, which is also worth asking about wherever you're shopping.
Bin wall thickness
Material thickness is the definitive measure of robustness; design matters, but steel is steel. Get the plate specs in writing rather than accepting a brochure adjective. For reference, Davimac runs 6.4 mm plate on the front, back and underside of the superstructure, 3 mm sides, and 10 mm auger flights against an industry standard of 6 mm.
Chassis
Look for solid chassis sections with additional material where it's needed: at joins, transitions and bends where stress concentrates. Davimac chassis are built from 10 and 16 mm plate with heavy RHS sections (up to 350 x 350 x 16 mm on the 45T), and if a walking beam tandem is under consideration, check how the beam axle mounts to the chassis, because that junction carries the load.
Finish
Paint isn't cosmetic on a machine that lives outdoors with grain dust and fertiliser around it. A quality coat prevents corrosion, keeps the bin easy to clean and holds resale value. Two-pack over proper preparation is the industry standard; Davimac bins are finished in 2-pack automotive paint for resistance to weathering, scratching and chipping.
Clean-out
Cleanout problems happen where flat surfaces, struts and bolt heads protrude inside the bin and hold grain. Look for a smooth internal finish, steep bin angles with no flat sections for grain to sit on, and doors that operate easily and lock positively. Davimac bins run six cleanout doors across the full bin length, opened and closed with a single lever at the rear, and the outload auger has a low access point for clearing the last of the grain.
Why Load Height Matters
A lower bin fills easier and tows safer. Lower sides mean the header operator isn't threading grain into a narrow target at full stretch, which cuts spillage from high-output fronts and reduces the risk of the header auger clipping the bin. A lower profile also drops the centre of gravity, which you feel on side slopes and in transport.
Davimac 25T to 35T bins have a side fill height of 3,310 mm, achieved with a long, low bin profile rather than by shrinking capacity. When comparing brands, compare fill height at equivalent capacity; a short bin that gives up tonnes isn't a saving.
5. Running Gear and Hitching
Tyres
Tyres should be load rated for the bin's full weight; if that rating isn't offered up front, ask why. Consider footprint as well as rating, because contact area is what manages compaction. Davimac bins ship on Australian-engineered Harvest tyres with optional Trojan R3 800/65 R32 high-flotation rubber for softer ground. Buying second hand? Check condition and look for radial cracking before money changes hands.
Rims and wheel nuts
Rim damage and loose wheel nuts are among the most common chaser bin faults found in the field. Torque wheel nuts to the manufacturer's spec and re-check through harvest; wheel nut indicators are a cheap addition that show movement at a glance and change colour when a hub runs hot. Davimac bins run 12-stud hubs across the range.
Wheel centres
If you run controlled traffic, wheel centres are the spec to check. Davimac 25T to 35T bins are factory set at 2.56 m for transport and jack out to lock at 3.0 m centres to match CTF systems; the 45T runs fixed 3.0 m centres with its steering axle. We cover tyre choice, flotation and compaction in detail separately (tracks vs tyres, week 5; add link on publish day).
Hitch and tongue
Look for a heavy, braced hitch underside and check the drawbar load the bin puts on your tractor: Davimac loaded tongue weights range from about 2,200 to 4,800 kg by model, with full figures on the specifications page. A rubber-cushioned drawbar absorbs shock across rough ground instead of feeding it into the chassis and tractor, and Davimac's swivel tow-eye hitch has a changeable ball (1 inch and 1 3/4 inch) to match your drawbar pin. If a smaller front wheel assist tractor will pull the bin, a tandem axle unit is the safer pairing above 25 tonnes.
Jack stand
Unhitching a loaded bin is when a flimsy jack shows its quality. The stand should hold the bin solidly at full weight, raise and lower without a fight, and stow cleanly out of the way. An adjustable jack stand is standard on every Davimac.
6. Equipment and Options Worth Having
Scales
Load cells with an in-cab indicator turn every unload into data: you know what left each paddock and what went on each truck, which matters for both agronomy and road compliance. Kondinin's assessment is the same: if the budget stretches, scales are a real asset for filling trucks accurately. Paired with the Agrimatics Libra Cart system, the data lands on your phone, and a 2026 upgrade adds automatic gate control to unload a set weight into the truck without touching the lever.
Cameras and lights
On a purchase of this size, Kondinin's researchers see little excuse to skip a proper camera and lighting package, and harvest hours agree with them: weather windows don't respect daylight. Big bins are also difficult to reverse safely, so a rear-facing camera earns its keep outside harvest too. The Davimac camera kit runs three cameras (rear, into the bin, and top of the auger) on a 9 inch in-cab monitor, and every bin ships with twin 48 W LED auger lights putting 6,000 lumens exactly where the grain lands.
Fire fighting equipment
The best fire fighting unit is the one you have with you, and during harvest the chaser bin is always close to the header, which is where fires start. Many farmers rig their own tank and pump; a factory unit does it without the fabrication. Davimac's option mounts a 400 L tank, pump and 36 m hose on the front of the bin, with a 9 L air/water extinguisher available alongside or instead.
Roll tarp and grain sampling
The tarp should operate and stow securely, with a handle that stays put over rough ground; check the locking mechanism before you buy, and make a habit of rolling it back before outloading. Davimac fits a 900 GSM PVC-reinforced roll tarp as standard. A grain sampling valve, also standard, is a simple addition that makes collecting a sample safer and quicker than climbing the bin with a jar.
Ladders and internal access
Operators end up inside bins, whether manufacturers plan for it or not: final cleanout, servicing, a blocked auger. Better to make entry safe than to pretend it won't happen. Davimac bins include a side access hatch, ladder and welded internal foot platforms, plus two 6 mm Perspex windows in the front of the bin and one at the auger base so the operator can verify gate status and grain level from outside.
7. Servicing and Maintenance
Machine longevity is a function of how easy the machine is to service, because accessible grease points get greased. Check where they are, whether any need acrobatics to reach, and whether wear parts are bolt-on replaceable or welded in (Davimac's are bolt-on). Clear safety decals with suggested lubrication intervals sound trivial until the third casual operator of the season is doing the greasing.
The performance of older bins can often benefit from a refurbishment which can extend the machine's working life and provide access to newer technology and features.
8. Transport Logistics
Transport width
Check transport width before you buy, not after, and check the folded outload auger doesn't make the bin overwidth on its own. Davimac 25T to 35T bins measure 3,480 mm wide with wheel centres retracted to 2.56 m, a profile that doesn't require a transport escort. The 45T is a wider machine at 4,210 mm, so plan its movements accordingly. Every bin ships with a road transport kit: oversize signage, flags, amber beacon and LED tail lights. Overall widths and transport speeds vary with tyre selection, so confirm your configuration against current requirements in your state before travelling.
9. Support After the Sale
A chaser bin is a 20-year purchase, so weigh the manufacturer's support the same way you weigh the steel. In Kondinin Group's 2024 National Agricultural Survey, Davimac owners rated their bins 9.0 out of 10 for build quality, 9.0 for ease of operation and 8.5 for reliability, among the strongest scores in the survey. Davimac bins are built in Central West NSW, backed by a factory warranty, a national dealer network, an online spare parts store and a manuals library, and parts are stocked for current and legacy machines.
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Quick Answers
What size chaser bin do I need?
Size the bin to hold at least two full header grain tanks, matched against your truck capacity and crop density, and compare models volumetrically (in litres) rather than by badge tonnage. Single-header operations typically run 25 to 35 tonnes; multi-header operations and long carting distances justify 35 to 45 tonnes.
Should I buy a single axle or dual axle chaser bin?
Single axle bins (25 to 30 tonnes) are lighter, simpler and cheaper, suiting firm country and smaller headers. Dual axle bins (30 to 45 tonnes) spread weight across four tyres for less compaction and smoother towing, and suit heavy soils, CTF systems and bigger operations.
How fast does a chaser bin unload?
Davimac chaser bins unload at up to 12 tonnes a minute with a 20 inch auger, and up to 18 tonnes a minute with the 24 inch auger on the 45T, using PTO drive at 1,000 rpm. Actual rates vary with crop and discharge setup.
Do chaser bins need an escort on the road?
Davimac 25T to 35T models are 3,480 mm wide with wheel centres retracted, a transport profile that does not require an escort. Wider machines like the 45T need movement planning under state oversize rules. Always confirm current requirements for your state before travelling.
