Like the proverbial Swiss army knife, there’s a lot expected of a 100hp tractor. On small and medium farms they invariably act as front-line workhorses and even large-scale operations often rely on them for lighter jobs. More than 2000 tractors in this class were sold in the UK in 2008.

What are the real capabilities of these 100hp machines? To find out, we used the machines in the field and asked the DLG (German Agricultural Society) to test things like power output, torque rise, fuel consumption, lift capacity and noise.

We invited all the leading manufacturers to send their machines for comparison. Seven companies accepted our invitation and sent us the contenders pictured on these pages.

We wanted to test the Claas Axos with its Perkins engine but Claas wasn’t able to supply an Axos for comparison and the new Arion 400 wasn’t available at the time.

At our request the manufacturers delivered the tractors with a loader of their choice. We wanted to judge the performance of the tractor during handling work – not the performance of the loader itself.

Interestingly, the difference between the cheapest and the most expensive tractor in the test group was a massive €27,000 (£24,405). Bear that in mind when you read the test results.

Engines

The DLG’s pto power test showed that transmission losses at the pto meant recorded power was lower than the rated measurements manufacturers quote for an engine running on the bench.

Settings had to be within a permitted tolerance range of ±5%, so the engines could not be tuned or chipped.

The DLG also ran an exhaust test for nitrogen oxide content, designed to show if an engine might have been “prepared” for the test by running with altered injection timings. All the tractors had between 23 and 129 hours on the clock and all had air brakes (standard in Germany) and air conditioning.

Even with mechanical injection, some of the tractors (such as the New Holland) achieved the requirements of Tier 3A emissions regulations. Fendt’s Deutz engine represented the other extreme of the engine sophistication scale with common-rail injection, intercooling, viscous-fan, externally cooled exhaust gas recirculation and 4-valves/cylinder.

Tractors in this class seldom have power boost. The MF was the exception, with boost activated in pto work as well as in third and fourth range. The boost could not be switched off so the DLG could only test the MF 5445 with it activated.

Fuel consumption

The DLG measured consumption in g/kWh. At a given rpm the most economical tractor sipped just 258g/kWh while the thirstiest guzzled 314g/kWh Ð a difference of 20%.

The Fendt 310 Vario was particularly efficient here with 270g/kWh. Then there was a gap, with the New Holland coming in at 282g/kWh and the Deutz-Fahr with 287g/kWh. Thirstiest here was the Perkins engine in the MF, consuming some 20g/kWh more than the average.

All tractors were tested for draft performance with the same tyres (540/65 R38). Performance laid down at the wheels depended mainly on drivetrain efficiency.

The average loss when comparing pto output with draft performance was 15hp. With the Valtra only 10hp was lost and in the worst case up to 24hp of the New Holland’s power disappeared.

The difference with the Fendt’s stepless transmission was 17hp. But such figures only offer a rough idea of drivetrain efficiency (the lower the pto loss, the worse draft efficiency appears).

Transmissions

Though tractors of this size are very much built to a price, most still manage to offer operator-friendly gearboxes. The Fendt’s Vario box offers maximum versatility but seems overly complex for this type of machine.

John Deere and Valtra offer easy operation with their automatic powershift programmes. MF’s Dyna-4 transmission is completely electro-hydraulic so that all speed changes (including range shifts) can be made without the clutch with either right or left hands (via the shuttle lever). This allows the right hand to stay with the front loader joystick – ideal.

All tractors had a powershuttle lever as standard. MF and Deutz-Fahr allow its aggressivity (ie its sharpness or softness) to be adjusted to suit the work in-hand – another big plus-point.

Cabs

Access is important and the cab should not be so high that low entrances are a problem. Good visibility is vital for loader work too. Turning circle tests were carried out on concrete without 4wd engaged and the circle measured from the outside of the front wheels.