Test Drive: Mercedes-Benz Atego UNVI Voyager GT

With Vario now but a distant memory, Mercedes-Benz’s midicoach platform at Euro 6 is the Atego. Chassis were slow to arrive at bodybuilders, but since then several have brought products to market. UNVI is one, with its Voyager GT. Tim Deakin drives one.

The Atego chassis is Mercedes-Benz’s only offering in the midicoach sector at Euro 6, and is available in this application at GVWs of 9.5-15 tonnes. Several bodybuilders have unveiled new products mounted on lighter variants, and Mercedes-Benz promises much of its all-new driveline.

To complement its existing 15-tonne GVW Atego-based Touring GT, which seats up to 41, UNVI launched the Voyager GT at last year’s Euro Bus Expo (EBE). It is mounted on a 10.5-tonne GVW Atego.

Compared with its Vario-mounted predecessor, the Touring GT is not significantly larger, and the manufacturer has successfully attempted to retain small coach styling.

UNVI initially expected to offer the Voyager GT on both 9.5- and 10.5-tonne GVW chassis, but all production midicoaches will now be built on the heavier variant to simplify the build process and maximise luggage capacity.

The Voyager GT is available at a variety of specifications, both internally and within the drivetrain, and has been modified since the prototypes debuted. UNVI’s UK dealerships report strong operator interest in the new model.

Brian Ferguson and Gordon Robertson, of Whitburn, West Lothian-based UNVI supplier Coachtraders, kindly made their demonstration vehicle available for a routeone Test Drive.

 

Build

UNVI has elected to position the Voyager GT’s door behind the front axle. Gordon explains that, at the design phase, UK dealers were involved in this decision, and that placing the door ahead of the axle was also considered. All consulted agreed that behind the axle was preferable.

During the period between the prototypes’ EBE debut and the appearance of production versions, UNVI took the opportunity to slightly revise the layout around the engine hump. This included moving the radio, DVD player and tachograph units to more accessible and less damage-prone locations.

Beneath the substantial cover lies a four-cylinder, 5.1-litre Mercedes-Benz OM 934 engine. Design life is 750,000km, while Mercedes-Benz claims fuel economy will be excellent and performance impressive. In the Voyager GT, it’s available at three ratings: 211bhp and 231bhp in stock chassis, and 177bhp to special order.

The highest output has been specified by Coachtraders in its demonstrator. Customer orders have been split between the 211bhp and 231bhp ratings so far; Gordon reports no interest yet in the 177bhp setting.

The OM 934 is coupled with the six-speed PowerShift 3 automated gearbox, although a six-speed manual is available. The test vehicle’s ULW is 7,290kg, giving a 3,210kg allowance for 30 passengers, the driver and luggage.

As a front-engined chassis, boot space on all Atego-based midicoaches is good. The Voyager GT has a manually-operated parallel lifting door, although Brian and Gordon explain that UNVI is exploring a powered option. Additionally, the boot can be accessed from the nearside. Luggage can also be stored in modest side lockers.

Large rear window has reversing camera above; Voyager GT has an UNVI family aspect
Large rear window has reversing camera above; Voyager GT has an UNVI family aspect

 

Passenger access

When open, the door does not overlap the opening in any way – not the case on many other coaches. The wheel arch encroaches slightly into the lowest step, however.

The Voyager GT’s sunken gangway is reached via four steps, with the top one being substantially shallower than the others. Handrails around the entrance are easily reached, and the Masats door mechanism will also inevitably be used as a handhold by infirm passengers.

Both the gangway and entrance step edges are lined in blue LEDs, although none of the steps are marked in high-visibility yellow.

At the rear emergency door, a modest in-built ledge extends to assist passengers alighting here. No evidence of any wind intrusion around the edges of either door was found even when at motorway speeds.

Seats in the main area are easily reached. The single nearside front position is slightly more awkward to access, but the effort is worth it. Legroom and the view, both to the front and the left, are excellent.

Doorway is wide enough, although door panel would benefit from more glass
Doorway is wide enough, although door panel would benefit from more glass

 

Passenger comfort

Coachtraders has opted for a high internal specification, and 30 full leather Brusa seats with three-point belts are fitted.

Those in the aisle have a slide-apart function, although when this is deployed in two adjacent seats the gangway becomes narrow.

The 30-seat layout incorporates an extended boot, with the back row mounted around two feet ahead of the rear wall. A parcel shelf is behind.

An alternative layout includes an additional four seats, with the rear bench tight to the back wall. This reduces boot capacity, so operators thinking about taking a Voyager GT will need to give thought to which layout suits their needs best.

The single front seat was initially expected to act solely as a courier’s position, but UNVI has successfully certified it to carry a passenger. Courier facilities such as a microphone connection, USB charging port and power socket remain nonetheless, and it suits both uses.

One notable oversight on this seat is the position of the belt. It is to the nearside, and as a result the upper bracket fouls the window pillar when the seat is reclined. This makes returning to the upright position difficult without a solid pull on the backrest.

UNVI’s standard touch-screen unit is provided in the cab, and this governs (among several other things) saloon climate control.

No auxiliary heater is fitted, but one is available as an option. Perimeter radiators are present as standard. Passenger service units are fitted, incorporating air-conditioning outlets.

The industry standard Bosch Professional Line entertainment system is fitted, incorporating a DVD player. A single monitor is above the gangway at the front; it drops manually. Where operators specify tables and the resulting rear-facing seats, a second monitor will be provided at the rear.

Demonstrator is highly-specified inside, but less luxurious fittings are available along with two boot sizes
Demonstrator is highly-specified inside, but less luxurious fittings are available along with two boot sizes

 

Driver comfort

As a front-engined midicoach, the cab is naturally less roomy than if the power unit was at the rear. With the driver sitting as far forward as is possible – the curved windscreen is very close indeed – the engine is immediately to his or her left.

There is still a reasonable amount of space, although storage for a bag and accompanying bits and pieces is limited. Surprisingly, a coat hook was not fitted to the test coach.

The driver ordinarily enters from the offside, and two very shallow steps are provided here. The door opens widely enough, but only has a hand-hold on the right. If necessary, he or she can also enter via the passenger door and climb across, although naturally this is a little tricky.

At the offside door, the handbrake lever is positioned where the driver may grab it when boarding, which could lead to problems if it is damaged. UNVI is aware of this and a second handrail is being sourced, says Gordon. An air-suspended seat is provided, and within the driver’s door is an electrically powered signalling window. The section of glazing adjacent to the offside mirror is heated; that through which the nearside mirror is viewed is not.

A small, lockable compartment is provided behind the seat on the offside, to which the handbrake is mounted. A cup holder is present.

Cab is nicely laid-out, and has been improved from prototypes
Cab is nicely laid-out, and has been improved from prototypes

 

Performance

231bhp in a 10.5-tonne GVW chassis gives a power to weight ratio of 22bhp/tonne, equal to or better than many larger coaches. Brian and Gordon explain that, while 211bhp is ample for most applications, the higher setting will be beneficial for operators who encounter tougher terrain.

Gears are selected via a dash stalk. Two shift strategies are available in PowerShift 3: normal and economy, chosen via a toggle switch. The driving experience is for all intents and purposes the same as in a fully-automatic thanks to one very notable gearbox characteristic.

When its software detects that the vehicle is facing uphill, it engages the clutch as the brake pedal is released, meaning that it is simply not possible for the Voyager GT to roll back during a hill start.

Although good practice dictates that the handbrake should be applied, it’s not necessary to do so when moving away uphill. The software ensures a start will be made correctly without driver intervention, and as a result, no ‘hill hold’ aid is fitted.

PowerShift 3 is also good at judging terrain and making optimal use of its six ratios. It selects either first or second to move away, and block shifts on occasion. Notably, it sometimes also selects neutral when freewheeling downhill with the cruise control engaged when a fuel saving may result; reselection of drive is instantaneous and almost unnoticeable.

Shift quality is easily judged by the driver in a front-engined chassis, and at no time was there any evidence of clunking or juddering. On this showing, PowerShift 3 really is as good as Mercedes-Benz says it is.

Equally impressive is the OM 934 engine’s keenness. Its 900Nm of torque is moderate, but developed from a low speed, meaning that progress is rapid when it needs to be.

Most impressively, when joining the M8 from a roundabout and via an uphill slip road near Whitburn, the Atego had reached its 62mph limited speed before merging with the main carriageway.

This was done without holding gears manually, and the ‘box shifted up at the top of the green rev counter band as normal. Of particular note is performance in the top two ratios. It is very happy to dig in and piles on road speed from 1,100rpm onwards.

A variable cruise control and speed limiter is fitted, but it is important to realise that, in economy mode, cruise control cannot be set any higher than 53mph.

That gives away the Atego’s origins as a truck chassis, but it is easy to deselect economy when required.

At 62mph in sixth gear, the OM 904 is turning at 1,800rpm. This means it will also hold top gear at 40mph, benefiting economy; at this road speed, the engine is spinning at around 1,100rpm, and is quite happy to do so.

Frontal styling has changed since the model debuted; a small bonnet complements interior hatch for engine access
Frontal styling has changed since the model debuted; a small bonnet complements interior hatch for engine access

 

Verdict

With the 231bhp rating, the Atego in midicoach form is a highly competent chassis. Its performance is keen, and, albeit empty, over a mixed route a fuel return in excess of 18mpg is excellent, and approaching Vario territory.

In the Voyager GT, UNVI has produced a body which incorporates many aspects of a big coach feel while largely retaining the dimensions of its predecessors.

Coachtraders’ high-specification demonstrator creates a good impression, but a more basic, higher-capacity example was present at its premises awaiting delivery when routeone visited. While not as well appointed, it is more than suited for either day work or shorter-duration tours.

The door’s location behind the front axle improves access immeasurably and the passenger environment is good. UNVI also offers a variety of optional fittings, not least a floor-level toilet.

However, the Voyager GT is not a perfect vehicle: the highly curved windscreen means that visibility through the mirrors is not as good as it could be, and it also eats into cab space. One or two other, minor, issues are being addressed by UNVI.

These niggles aside, the Voyager GT is competent. It joins a congested midicoach market, but is already selling well despite the volume of competition and continues to attract strong interest. That should tell its own story.

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