Review: Mercedes-Benz E 300de plug-in hybrid AMG Line

Motoring correspondent Mark Gallivan test drives the new 2020 Mercedes-Benz E 300 de Plug in Hybrid AMG Line, a critical addition to the car giant’s fleet.

Mercedes has facelifted the executive class E-Class range for 2020. It’s a critical car for Mercedes and globally 1.2m buyers bought the previous generation car.

Of interest to business users are the updates to the E Class hybrids with either petrol or diesel plug-in now offered with larger batteries. The challenge with all petrol hybrids is the inferior economy against a diesel PHEV engine when the battery charge is used up and you’re relying on petrol power alone.

“It still defies logic that a heavy 2.0 litre four-cylinder diesel four door executive car like this can thrust itself from 0-100 km/h in 5.9 seconds. That is two-tenths of a second slower than the original Lamborghini Countach”


Mercedes has added extra battery capacity with this facelift so this was a test of actual fuel economy versus the marketing claims derived during optimal conditions.

Power and performance

The 300de I tested was €64,459 300de Plug-in-Hybrid with AMG line trim. It still defies logic that a heavy 2.0 litre four-cylinder diesel four door executive car like this can thrust itself from 0-100 km/h in 5.9 seconds. That is two-tenths of a second slower than the original Lamborghini Countach. This E is deceptively quick off the line with a thumping 700Nm and yet emits just 33g/km with €170 road tax.

The claimed hybrid consumption figures are, as ever for hybrids, fantastical and Mercedes says 1.4 l/100 km or 168mpg is achievable and we would applaud them for this achievement. Apart from the fat-chance-you’ll-ever-get-that bit. I squeezed just over 50mpg running diesel engine power only with a depleted battery on a continuous motorway stretch. That’s a decent enough return with a car this large and heavy. Buy the petrol E Class PHEV you’d be very lucky to ever see the far side of 40mpg once the hybrid battery was used up. Expect 35mpg as the more accurate prediction which is where this test becomes pertinent to business users doing large annual miles.

The EQ warmed E Class diesel hybrid saloon is on sale with prices ranging from €65,615 to €67,740 (SEAI / VRT combined support of €7,500)

For 2020 the battery is increased from 6.2 kWh to 13.5 kWh with the promise of limited of pure electric driving. If you drive this new E Class hybrid or are considering an executive PHEV like Audi’s A6 and BMW’s 5 Series recently introduced hybrids chances are you may play golf. In hybrid form the boot space drops from 540 to 370 litres adding 260 kg weight to store the battery. The boot’s floor is and awkwardly stepped construction and reduces the loadspace capacity.

Changing mindsets

Inside a Mercedes E Class 2020.

What I wanted to discover was how smooth the diesel/electric combination was and if it could reverse the trend of ditching a diesel engine altogether and going petrol.

The E-Class is fitted with a 9G-TRONIC gearbox and the way the auto slurs between gears is an improvement. The transition from diesel to battery power is hardly noticeable and well suppressed.

The face lift is subtle with a new front grille and headlights/taillights with standard LED illumination, bonnet bulge and slimmer rear headlights. Inside the cabin gets panoramic digital displays, MBUX voice command and the introduction of one of the fiddliest central touchpads I have encountered. Only Lexus’s touchpad does this key functionality worse. The perfectly usable rotary controller from the last generation worked fine and it’s beyond me why it was replaced here. There is also a new steering wheel with scrolling functions replacing the small chrome knobs. While it’s not a step backwards it isn’t as frequently intuitive as you’d think.

Things brighten up with the new seats and moderately tweaked cabin design. The seats are firm but supportive covered with artificial leather as standard. The cabin leads the pack with swooping designs that has the hallmarks of the old S-Class, which is a good standard to mimic.

I had the test car over four days and found the more I drove it the more satisfying it became. The Mercedes does better than BMW and Audi for ride composure and pips Volvo for smoothness. Like all non-AMG Mercedes products the target is composure and compliance with a veneer of sporting feel. It’s worth mentioning that the car’s suspension does get caught out on uneven surfaces at low speeds. Where the E-Class fares best is motorway cruising and managing big trips in one sitting without crippling the driver and passengers. The E-Class in electric only is eerily quiet and compliant. I have yet to test BMW and Audi’s equivalent hybrid so a verdict on who does best here remains conjecture.

Then there is the Mercedes X factor. As compelling as rivals are the image of a Mercedes three-pointed star on your grille still cuts plenty of ice with people. It’s hard to pin down but a new Mercedes exudes an intangible aura of quiet respect from other road users.

Objectively the face-lifted Mercedes E300de picks up the gauntlet of economy, thrusting power and eco friendly hybrid tax breaks into one executive saloon and ticks all those the boxes well. If you can stomach the not insignificant €64,549 that Mercedes pegs the E300de and it is a great luxury executive PHEV. Crucially the longer you drive it the more appreciative you are for owning one. Get yourself a dedicated home charger and the refreshed Mercedes with diesel hybrid power now makes more sense than ever.

By Mark Gallivan

Published: 14 October, 2020