G OOD M OV E
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Anything new from M-B is bound to be com pared with the latest Sprinter, Vito and the Actros. it is unfair—but inevitable. The new 7.5 tonne 814 falls far short of the innova tion to be found on those three, nevertheless it exploits a market that is being shaped by the recent licence changes.
Ii's almost a disappointment to he faced with a Mercedes-Benz that is not an allnew model. Since the arrival of the Sprinter, the Vito, and then the Actros we have come to expect great things from the designers in Stuttgart. But externally, at least, there is little to distinguish the 814 from its predecessor. Apart from a smaller radiator grille all we get is a new engine and gearbox. Still, mustn't grumble,
To be fair, an all-new 7.5-tonner will be launched next year as part of the LEiN truck range, for which the new engine was originally designed.
It might be thought there is little point in investing in this area of the market since the new licensing laws came into effect at the beginning of the year. These limit new car drivers to 3.5 tonnes so fleet buyers might as well go for the better payloads of 10-tonners and above. However, there are few mechanical differences between a vehicle rated at 7.5 tonnes and one rated at 10 tonnes, so although the market might change subtly, it should continue to thrive, at least in the short term. • PRODUCT PROFILE The LN2 Ecopower light truck range spans the gross vehicle weight range from 7.5 tonnes to 13 tonnes. In 814 guise there are four wheelbase options (3,150mm-4,100mm); for the 814L with air suspension you get three wheelbases (3,700mm-4,900mm). Our test model was the 4,250mm wheelbase 814, which is driven by the 134hp (100kW) variant of the new 0M904LA four-cylinder engine. This fits in towards the bottom end of the market, being slightly more powerful than the Volvo 133hp (99kW) but giving away at least 10hp to the MAN L2000 or the Nem Cargo.
Launched in January last year, the fourcylinder charge-cooled and wastegateequipped diesel replaces both the 0M364 (four cylinders, 3.97 litres) and the 0M366 (six cylinders, 5.96 litres). It is available in three states of tune: 122hp (90kW), 136hp (100kW), and 168hp (125kW) — as found in the 7.5tonne 817. The engine offers substantially more torque than earlier models, producing 3831lift (520Nm) at 1,200rpin 1,500rpm for the 136hp variant. A Konstantdrossel (conlor stain throttle) exhaust brake is an option in the UK but was not fitted to our test model.
Euro-2 emissions regulations demand high injection pressures: the Mercedes approach is to use unit pumps (one per cylinder), driven by the camshaft via roller tappets. Short pipes go to electronically controlled injectors, vertically mounted in the centre of each combustion chamber. These are individually controlled to compensate for manufacturing tolerances and to reduce noise. The engine meets Austrian night-time driving regulations with a drive-by noise level of 78d13(A).
The gearbox is the ZF five-speed synchromesh, which is widespread in this market. The more powerful 817s get Mercedes' own six-speed G 60.6 as standard—this is optional on the 814.
A further option is the sleeper cab, which has a single passenger seat, a roof vent and two bunks with stowage space.
• PRODUCTIVITY With a full tank of petrol but no driver or box body the 814 weighs 3,135kg, leaving 4,365kg for the body/payload (our test vehicle grossed at 7,475kg). This is on the heavy side of the market and roughly the same as the Volvo. It gives away 258kg to the Iveco (4,623kg) and 105kg to the MAN (4,470kg). Admittedly the Merc has a longer wheelbase than the MAN, but the Iveco clearly has the edge on payload.
Of the Euro-2 engines tested so far, the Iveco has proved the most frugal, returning a figure of 18.4mpg on our Welsh test route. The last time we tested an 814 it achieved 17.1mpg, with a windcheating body kit, so we were not too optimistic this time round. In fact it managed a pretty good overall figure of 16.9mpg, which is only slightly behind the MAN and beats the Volvo by a substantial margin.
The truck fared worst for fuel on the motorway section where it had to work to maintain 70mph. But its A-mad performance was better than the MAN's, suggesting that the gearing is more suited to urban work.
Having said that there is nothing wrong with the average speeds. The overall speed of 71kmili is only marginally behind the MAN and the Iveco.
Although the drop in fuel economy is only slight, it does mean that the environmental benefits of Euro-2's cleaner emissions are somewhat offset by the fact that more diesel is burnt in the process.
Boalloy's box body is well finished and looks tidy. It features a translucent roof and roller shutter door. The load can be restrained by three rails down both sides and two at the front wall.
• ON THE ROAD The 814 rides and handles extremely well and anyone moving up from a smaller van should have no problems. Body roll is not too noticeable thanks to stabilisers on both axles and the parabolic springs front and rear react smoothly and absorb all bar the worst potholes.
For the most part the gearbox is well suited to keeping the truck's momentum up while staying within the green band. Changes are light and precise. However, the gap between fourth and fifth cogs is too large and to get there without backtracking you often find yourself winding the revs up to 2,300rpm. It could do with a sixth gem-. If you are in town it is usually a good idea to stay in fourth until YOU can see dual carriageways ahead.
The box is well suited to running at the 50mph limit where the needle stays at around 1,650rpm in top. This is about right for power and economy.
The new drive-by-wire was pedal is restrained by a coil spring that gives a light level of resistance. This is in contrast with the high-set clutch pedal, which is a tad on the heavy side.
The position of the park brake on the dash board to the right of the steering wheel is suitably trucklike, but for a van driver who is graduating to a 7.5.tonner it is a bit odd at first.
Initially it can tempt you to move off "nohanded" as your left hand is preoccupied with shifting to first. Most standing starts will need this gear unless you are on a slight downward slope,
Track testing shows the 814 to be average for the class on acceleration. The increase in torque was not enough to move it up the 1-in-3 hill but the park brake worked fine on that gradient.
The brakes themselves are not exactly whiplash-inducing but they are nigh on impossible to lock up and the truck pulls up in a straight line. It certainly doesn't cry out for an exhaust brake, which is probably a luxury in this installation.
111 CAB COMFORT Apart from the new accelerator pedal and diagnostics downloading plug there are few changes to the interior, which is spacious and airy. The seals are comfortable and decked out in the daring colours we have come to expect from Mercedes. The passenger bench seat comes as standard but a single one can be specified.
Stowage is more than adequate: there is a lockable glove box with two cup indents; driver's door pocket; full-width document bin behind the seats, lockable document box, sliding table lid, and a further cup-holder/oddsand-ends-compartment.
The indicators, main beam/flash, wipers and horn are operated from a single stalk to the right of the steering wheel. This will not he to everyone's liking and it is quite possible to blast unsuspecting pedestrians while going for the wipers.
However, the dials are all well positioned and easy to read. The rev counter is in the middle of the dash and a combination dial is to the left housing oil pressure, temperature. fuel and air pressure gauges.
Visibility is good both in the front threequarter view and in the rear view thanks to decent-sized door mirrors.
• SUMMARY We have now tested all the Euro-2 7.5 tonners except the Leyland Daf and the standard has been excellent. The 814 is no exception. Its engine has proved itself the most refined in the class although the five-speed gearbox (with a final drive geared for A-roads) does it no favours in terms of fuel economy The optional six-speed box is worth a look at £564.
With such a modern engine we are almost tempted to withhold judgement until the new LI{N cab is launched next year, but in its present form the 814 shows what can be done through development alone.
The other factors that set the Mercedes apart are ride and handling, both of which are exemplary. The areas where it is slightly let down are performance and fuel economy. These are by no means bad, but are beaten by the MAN and Iveco, The absence of a sixth gear may be partly to blame for performance.
Despite the age of the cab, it doesn't feel dated, and as you might expect build quality and finish are both more than adequate.
The 814 is unlikely to topple Iveco's Cargo from the top of the sales league but it certainly holds its own against its other main rivals. In the meantime we look forward to our next "new" Mercedes road test.
by Charles Young