By combining a diesel engine with an electric motor, the Mercedes-Benz E300 BlueTec Hybrid is not aiming to mimic Japan’s hybrid trailblazers but to effectively redefine luxury hybrid performance.
Mind, Benz isn’t the first to value diesel over petrol for hybridisation. That honour must go to Peugeot, which first married diesel and electric in 2009 with the launch of their 3008 Hybrid4.
But in the luxury car segment, the Mercedes-Benz E-Class diesel hybrid still represents a genuine game-changer. And the numbers certainly are impressive.
The E300 can accelerate from 0-100km/h in 7.5 seconds and on to a top speed of around 240km/h. Nothing remarkable there necessarily, though fuel use is certainly noteworthy – a claimed 4.3L/100km on a combined cycle.
Not bad for a 1.8-tonne luxury sedan. That shaves 0.6 litres per 100km from the regular E250 diesel and, on paper, is actually better than many small city cars, including the Honda Jazz Hybrid (4.5) and Smart ForTwo (4.4).
In reality, however, the best we could achieve was around 7.1L/100km, but in mostly urban surrounds - where hybrids typically excel.
Priced from $108,900 (before on-road costs), the E300 Hybrid sits third from the top in the E-Class hierarchy; below the range-topping E63 AMG S ($249,900) and E400 ($128,900) models, but $10,000 above the similarly specced E250 CDI that uses the same 2.1-litre twin-turbo diesel engine.
With the 20kW/250Nm electric motor, though, combined total output for the E300 is 170kW and 590Nm – the latter from an impressively low 1800rpm.
Outside, the Mercedes-Benz E300 Hybrid is as visually stunning as the rest of the E-Class model range. There’s an aggressive front splitter with dual pipes at the rear and side skirts. In fact, the only way to tell this is a hybrid is the by the nameplate on the boot lid.
There’s the usual diesel clatter on start up, but moving off or gentle throttle applications require electric power only.
Similarly, low-speed manoeuvres such as shopping mall cruising and parking will be met with an uncanny silence (except for a subtle whirring noise) as the E300 BlueTec Hybrid runs purely on electric power. Despite this, there is oddly no provision for drivers to switch the hybrid Merc solely to electric power.
Thankfully that same economy-busting hybrid technology also has other benefits – like getting the E300 off the line with a significant dose of extra grunt.
From the very instant you sink the boot in, there’s a full 250Nm of torque available from zero rpm, making for particularly quick standing starts when required.
Mid-range acceleration is particularly robust, with all 590Nm of torque providing plenty of shove as well as safe high-speed overtaking performance on the open road.
The hybrid powertrain is mated to the same seven-speed automatic gearbox used throughout the model range, though the E300 swaps the standard torque converter for a wet clutch, meaning it's not all smooth sailing, at least in start/stop traffic and hill climbing situations.
Even when you’re pulling away, the take-off can be occasionally jerky and there’s some careful throttle calibration required on some steep slopes in order to maintain a degree of smoothness when creeping forwards.
Once up to speed, though, the E300 hybrid Merc is capable of coasting at speeds of up to 160km/h with the diesel engine switched off and the speed maintained by the electric motor – until the lithium-ion battery pack needs recharging of course.
The default drive mode is somewhat understandably labelled as ‘Efficiency’, but drivers also have the option of a ‘Sports’ setting that effectively holds the gear ratios longer before shifting up. The penalty is increased engine noise, but it’s not over the top.
The whole hybrid thing works seamlessly, though. And apart from the usual diesel clatter sometimes heard at idle, this is a relatively quiet car on the whole with minimal noise intrusion inside the cabin under normal driving conditions.
Handling isn’t bad, either, considering the Mercedes-Benz E300 Hybrid weighs in 100 kilos heavier than the standard E250.
There’s a bit more roll on turn-in, but you can still carry plenty of pace through bends with no shortage of confidence from the chassis and the nicely weighted steering.
The E300 also gets a regenerative braking system and, while stopping power is indisputable, the pedal feel takes some getting used to. On initial application, the system self-tests and pedal travel is longer than you might be used to, though shortening up immediately afterwards.
Ride quality is excellent – especially considering the E300 is fitted with standard 19-inch alloy wheels and a lowered sports suspension – providing a thoroughly cushioned ride over most surfaces including potholes.
The potent electric motor snuggles in between the engine and the gearbox, so there’s no penalty to pay in terms of space and practicality. In fact, pop the boot and you’ll find a commendable 540 litres of luggage space as well as generous rear-seat leg and headroom.
Up front it’s the same luxurious surrounds you’ll find in every other E-Class variant, with lovely black ash inserts providing a luxury look and feel about the cabin.
About the only thing distinguishing the hybrid from the others in the model range is a power/battery metre that replaces the standard temperature range in driver’s instrument cluster.
The leather buckets are certainly comfortable, but they’re not overly bolstered like the sportier variants in the range.
Like its E250 siblings, the E300 Hybrid is stuffed full of luxury equipment including highlights such as a high-resolution 7-inch TFT colour screen with reversing camera, satellite navigation, electric adjustment of the front seats and multifunctional steering wheel, LED headlamps, Active Park Assist, auto-dimming rear-view and folding driver’s mirror, leather upholstery and keyless entry.
There’s also an extensive list of active and passive safety equipment, including 11 airbags and a host of crash-avoidance technology such as Active Blind Spot Assist, Active Lane Keeping Assist and radar cruise control.
The Mercedes-Benz E300 Hybrid certainly ticks all the boxes when it comes to economy, luxury and solid all-round performance, making it a compelling proposition for the early hybrid adopters and luxury car buyers with an environmental conscience.
But despite its considerable credentials, you have to ask yourself whether the E300 is really worth the additional $10,000 on top of its E250 CDI twin.