What do you do when you’ve nailed the formula for a compact 240hp tractor that accounts for about half your annual sales? If you’re Fendt, you decide to change it.

Yes, after more than a decade as the go-to tool for upwardly mobile farmers and contractors, the 724 Vario has been treated to a major overhaul.

Gone is the 6.1-litre Deutz engine, replaced with a beefy 7.5-litre block from in-house brand Agco Power.

See also: On test: John Deere’s 6R 185 tractor

And, in place of the original two-range Vario transmission sits a new single-range Variodrive unit with variable automatic four-wheel drive.

Fendt’s quest to deliver more power, torque and payload has also seen the tractor’s dainty frame abandoned in favour of a longer, heavier-duty chassis.

The extent of these changes has led to a significant shake-up of the 700-series hierarchy, with the 724 demoted to mid-range status and two higher-horsepower models, the 726 and 728, being drafted in above.

The latter looks like a good match for bigger-boned rivals such as John Deere’s 6R 250, but it creates some significant blurring of the lines between it and the king of the 800 series – the 828.

To find out if this upscaling is a welcome upgrade, or a dilution of the 724’s winning formula, we got a drive in one of the first 728s to enter the UK.

This came in the fully loaded Profi Plus spec with most boxes ticked on the options list.

Engine upgrade

It might now wear an Agco Power badge, but the engine slotted in the Fendt 728 will still be thought of by many as a Sisu.

That’s no bad thing, as these power plants have a reputation for offering plenty of no-fuss power and torque, as well as excellent reliability.

However, it is worth noting that this is a brand-new 7.5-litre engine that’s been built specifically for the Gen-7 700s, not to be confused with the 7.4-litre engine used by Agco stablemates Massey Ferguson and Valtra.

Benefits include the ability to deliver high torque at low rpm, which helps reduce fuel consumption and make the tractor quieter.

On the road, this means 50kph is achieved at a sedate 1,200rpm, with the new option of 60kph reached at 1,450rpm.

It’s the same story in the field, with just 1,650rpm required to spin the 1,000-speed pto, which is about 250rpm lower than the Gen-6 724.

As the flagship model, the 728 gets the benefit of the firm’s “dynamic power” boost function, which gives it an extra 20hp to play with.

Unusually, this is available at all times, rather than being limited to when the tractor is travelling over a certain speed or the pto is in gear.

As a result, it’s almost fair to claim that it’s a 303hp tractor.

Another notable feature is the pressurised hydraulic cooling fan, which is similar to that used in the 1000-series.

Fendt says it takes 40% less power to drive than the old viscous arrangement and it seems quieter, too.

No range change

When it made its first appearance on the 1000-series back in 2014, it was inevitable that Fendt’s Variodrive transmission would filter down to smaller models.

The TA190 version fitted in the 700-series works on the same principles as its larger sibling, with independent drive to the front and rear axles via two separate hydraulic motors.

One of the most obvious improvements is that there is no longer a range change to perform when moving from field to road work.

But there are also some benefits to the sophisticated variable four-wheel drive system.

Cleverly, this balances power and torque between the front and rear axles to maximise grip, as well as offering a pull-in turn function that claws the front axle round to give a tighter turning circle.

It means the new Gen-7 tractors have a turning circle of 11.8m on 600/70/R30 tyres, which is tighter than the Gen-6s.

Bigger booties

For some, the updates to the 700s’ wheel and tyre offering will be welcomed with open arms.

For the first time, there’s the option of adding Variogrip central tyre inflation, which is a bonus for those that need to regularly flit between sensitive soils and tarmac.

Previously, buyers wanting this had no choice but to upgrade to the 800-series.

© James Andrews

Bigger rims and tyres are also available up to 710/70 R42s at the rear – giving an overall diameter of 2.05m – and 600/70 R30s on the front.

As a comparison, the biggest the Gen-6 724 could accommodate were lower profile 42in tyres with a diameter of 1.95m.

Cab refinement

Save for a few minor tweaks, the cab and controls are the same as the Gen-6 700-series.

Minor upgrades include the option of fitting a coolbox/hot box next to the right door, an ultra-fancy heated, cooled and massaging seat from premium brand Isri, and the option of integrated front grille and rear cameras that feed into the in-cab displays.

© James Andrews

As we’ve said before, the level of technology and customisation on offer is mind-boggling and most users will only ever scratch the surface of what it can offer.