There is a lot to consider when purchasing a tractor, not least are the many brands and options available. To help make sense of the terms used we have compiled and brief explanation to the various aspects of a tractor.
This one is pretty easy to compare between brands, speak to friends or neighbours that already have a tractor to determine what size you think you need, alternatively speak to your dealer and discuss your needs, expectations, available implements etc.
One thing to note is some manufacturers measure horsepower in different ways. There are several standards that are internationally recognized but they vary in the requirements. Some do not include the engine fan, alternator, water pump, oil pump and more so be mindful of this. In small tractors the difference is not usually enough to make much difference but as you get into higher horsepower you will notice the difference.
There are many options to consider when choosing a tractor and one of the most important is what transmission you want/need. I will try and explain each below.
- Hydrostatic – This is probably the easiest to drive, you will have either two pedals, one for forward and one for reverse or a heel/toe pedal where you push with your toe for forward and your heel for reverse. In either case, the further you push the pedal in either forward or reverse the faster you will go, regardless of engine speed. In a hydrostatic you will usually have 2 or 3 ranges to select from, this just gives you lower gearing for tackling hills or when towing trailers or draft equipment. Sometimes referred to as automatic as it is similar to an automatic car to drive.
- Collar shift – This is sometimes called a crash box, there will usually be 6 or 8 forward gears and 2 reverse, sometimes more, sometimes less. The gears will consist of 3 or 4 forward gears and reverse and then a high and low range. This transmission usually requires the speed matching of the engine speed and the forward speed to get a smooth gear change, once mastered this is not difficult.
- Synchro shuttle – This transmission has synchronised gear changes typically 8 or 12 gears made up by 4 gears in 2 or 3 ranges, then there will be a forward/reverse lever to select direction. Having forward and reverse gear matched means that when you shuttle between forward and reverse you will go the same speed in both directions, making it an excellent choice for loader work.
- Power shuttle – this transmission is very similar to the above synchro shuttle except you can change directions without using the clutch pedal.
- Powershift – This transmission allows all gear changes to be made on the go under load without the clutch. There is also Partial powershift which will have some gears being able to shift under load, on the go, without the clutch and some that still require the clutch.
- CVT – There are many trade names around for this type of transmission. While similar to a hydrostatic to drive, they all have a split of power inside the transmission and the majority or drive is still transferred mechanically, there is a hydrostatic component but it only influences the mechanical drive which offers greater efficiency. However, this type of transmission requires a high level of electronics and is rarely seen in tractors of less than 120HP due to costs.
Tractor manufactures will use different marketing terms for their transmissions, but all will fall into one or more of the above.
The hydraulic flow usually quoted in litres per minute (l/min) or gallons per minute. The hydraulic flow gives an indication to the speed the front end loader or rear linkage will lift at, it is also important if using rear implements that require a hydraulic input, such as post rammers, tip trailers etc. (the force or strength of the hydraulics is related to pressure which only varies slightly between tractors for a given size).
When comparing tractors, manufactures often quote steering and implement pumps separate, be wary of a figure that is combined as this will be higher but won’t give an accurate number for comparison. For example, a 50hp tractor will have around 20l/min for steering and 40l/min for the implement system (rear linkage, front end loader and spool valves if fitted) in this example the tractor manufacture can quote 60 l/min combined flow which sounds a whole lot better. Another reason a manufacturer will use a combined flow figure is there is only one pump, this works fine but your implement flow will drop off when the steering is activated. At the end of it the steering figure is completely useless to you as a high majority of tractors use the “left over oil” from the steering for transmission lubrication and activation of hydraulic clutch packs such as PTO, Forward/reverse if power shuttle, 4wd (if operated by a button) and more.
There are 2 main hydraulic pumps used on new tractors today. They are open centre or closed centre with load sensing (CCLS).
Tractors up to 100hp typically use open centre pumps. Tractors over 100hp will typically use CCLS.
Closed Centre pumps adapt to the demands of the tractor hydraulic system and only produce enough flow to match the demand, this leads to fuel and horsepower savings. Up to 100l/min these savings are minor and don’t usually warrant the higher costs involved.
The 3-point linkage is the rear (or front) linkage of the tractor. It consists of 2 lower links, and a central top link. Lift capacity will also be quoted and can be used to compare different models. Lift capacity will be quoted at the ball ends and/or a certain distance behind the balls e.g.24 inches/600mm. The figure behind the balls is more accurate and should be used when available as this is where the centre of the load is more likely to be. 600kg at the ball ends does not mean you will lift a 600kg slasher, more likely a 400kg slasher will be too heavy due to the centre of the load being so far back.
Some tractors will have the ball ends for category 1 and 2 combined which is a handy feature.
Tractor stability can be compromised with heavy attachments so be wary buying a tractor if you have an implement which is close to the maximum lift of the tractor. When operating the tractor with heavy implements make sure the front is suitably ballasted as well.
The rear linkage will be controlled either by position control or position and draft control. Small tractors up to 35hp will usually only have position control, larger tractors will have both position and draft control. Draft control allows the tractor to sense load on the rear lift arms and raise or lower the arms automatically. Imagine a plough behind the tractor and as the tractor pitches up and down due to the terrain the end furrow of the plough will be lifting or lowering a fair bit due to the length behind the tractor. As the plough digs in because the front of the tractor has moved upwards from a mound of dirt etc, the tractor senses extra load and lifts the linkage slightly maintaining the plough depth. If the tractor nose dips slightly the plough will lift up reducing the load on the tractor so the tractor will lower the linkage slightly. This balancing act continues.
Tractor linkages are categorized depending on the size of the pins required as per the table below:
|Category||Tractor HP||Top Link Pin Diameter (imperial)*||Top Link Pin Diameter (metric)*||Lift Arm Pin Diameter (imperial)||Lift Arm Pin Diameter (metric)|
|0||Up to 20||5⁄8 in||15.875 mm||5⁄8 in||15.875 mm|
|1||20 to 50||3⁄4 in||19.05 mm||7⁄8 in||22.225 mm|
|2||50 to 100||1 in||25.40 mm||1⅛ in||28.575 mm|
|3||80 to 225||1¼ in||31.75 mm||1 7⁄16 in||36.5125 mm|
|4||180 +||1 3⁄4 in||44.45 mm||2 in||50.80 mm|
There are 3 main choices for tractor tyres, Ag, Turf and Industrial.
Ag tyres have a more solid lug in a chevron pattern, this allows for self-cleaning and the best angle for forward traction and side traction. I.e. to stop a tractor sliding down a hill when traversing a slope.
Turf tyres have a wide relatively smooth footprint to reduce damage to the grass surface
Industrial tyres have a similar pattern to Ag but a wider tread bar and a firmer side wall.
Up to 50 horsepower approximately industrial tyres are the preferred choice as they offer a compromise between traction, floatation and surface area so they can still operate on fairly fine lawns and grass areas. Discuss your application with your dealer as there is not a one stop solution for everyone when it comes to tyre and wheel equipment.
Front end loaders
All front-end loaders sold in Australia have to be self-levelling, this means that as the loader is lifted or lowered the bucket or other implement will stay at the same angle. This is a safety feature that prevents the load in the bucket or other implement from tipping over the back as you raise the bucket and landing on the bonnet or operator.
You need to consider what attachments you want with the loader and if you require a third function or third service valve, this valve allows 4 in 1 buckets, hay bale grabs, post hole diggers etc to be operated hydraulically from the loader. This valve usually adds around $750 to the price of the loader.
Lift capacity is the next item to compare and in a lot of cases will determine the size of tractor you require more than horsepower alone. In Australia all loaders need to have a ROL rating, this is the Rated Operating Load, this is not what the tractor/loader can lift, it is what the tractor/loader combination can lift safely. The ROL will also advise the required counterweight to be fitted to the rear linkage to achieve the maximum lift. There is many factors that contribute to the ROL rating not limited to front/rear weight distribution, capacity of hydraulics, tyres, front axle, tractor laden weight and more.
It is common practice for one loader boom to fit multiple tractor models within a single manufacturer and also between other manufacturers so be careful if the loader lift capacity has been quoted as a generic value for the loader, it may not be safe when fitted to a particular tractor model.
Loader implement attachment. There are several mounting systems for the loader implement, check what is on offer for the tractor you are considering. This can add additional costs later on if you want a new implement. Euro hitch is fast becoming the preferred choice for manufacturers therefore has the largest range of “off the shelf” options some of the lesser used options may be slightly more expensive and/or less readily available. Euro hitch is a fast safe and secure way of attaching the implement.
This comes up a lot in new tractor discussions. We are or should be aware that electronics are everywhere, tractors are no exception. The upside to electronics are numerous and include:
- Ability to automate functions
- Reduce operator fatigue, e.g. A clutch can be controlled electronically to reduce operator effort
- Improve efficiency
Electronics are necessary to control modern diesel engines meeting high emission standards in overseas countries. Australia does not regulate off road diesel engines.
The downside to electronics is:
- They can be costly and time consuming to repair
- They cannot always be repaired without specialised equipment
Taking time to consider if the benefits of an electronically controlled tractor vs simplicity of repair should a fault occur should be made.
This is by no means a comprehensive explanation of each item, if you have questions, please contact us and we will be glad to assist.
One piece of advice I would like you to consider is that the tractor (brand, model, all of that) should make up 50% of your buying decision and the dealer should make up the other 50%. Things do break, or get damaged, and will require servicing, spare parts etc. Buy your tractor from someone who will be there when you need them, you can contact at times when you need them and have the support staff and systems in place to keep you going. We all too often get calls to come and service or repair a cheap imported tractor but we cannot get parts for them, if we try and call the importer we get referred to an online contact form that always comes back with a response to “refer to where you bought the tractor”. There isn’t any government department actively stopping grey imported machines with no spare parts support being brought into the country.
While all tractors are imported into Australia there are differences between the importing companies and this needs to be in your mind when looking at the cheaper alternatives.
Why listen to me? Put simply you don’t have to, but a little about me.
I have been working with or on farm machinery since I was 16. I completed an apprenticeship for agricultural machinery at a John Deere dealer involved with everything from lawn mowers through all sizes of tractors to combines and forage harvesters. Following my apprenticeship I worked for a large agricultural contractor operating machinery. I have also worked for one of the largest farm machinery manufacturers as a technical support area manager, again covering the full spectrum of farm machinery and equipment. So my experience covers everything from assembly of new machines as a young apprentice to operating tractors and harvesters of all types to repairs and diagnostics including behind the scenes for the manufacturer and technical training.