Disappointing in one respect. A 300bhp pseudo-performance SUV really ought to be more tantalising and enjoyable to drive than this.
The GLC 350 e, like all of Mercedes’ hybrid models to date, is the sort of car that’s at its best when driven unhurriedly. On more modest accelerator pedal openings, the electric motor copes well with the car’s two-tonne bulk. You’ll keep up with urban traffic easily, and maintain an A-road cruise without trouble.
But when you stretch the powertrain with wider throttle applications, the sheen comes off its style of delivery. Ask for full power and there’s often an unflattering delay before the combustion engine can wake up and supply it, followed by an unseemly lunge. Performance is strong in outright terms and powertrain response is better when the car is bowling along at more consistent speeds. But in manual mode, gearchanges can sometimes take a split-second longer than they should.
Brake pedal feel, a perennial bugbear of hybrid-electric cars that regenerate kinetic energy before activating their friction brakes, is also poor. Braking power ramps up suddenly beyond a certain point, and smooth progress can be tricky at low speed.
For keener drivers at least, other manufacturers offer more satisfying plug-in hybrid powertrains. But Mercedes may not worry too much about that, given that GLC owners will be used to making similar dynamic sacrifices relative to more agile-handling SUVs such as the Land Rover Discovery Sport and BMW X3. And given that the GLC 350 e, also like its rangemates, has strong practicality, commendable mechanical refinement and a fairly laid-back, cushioned ride to act as selling points.
The GLC’s high-voltage electric propulsion system is in effect noiseless from the driver’s seat. It’s powerful enough that you can quite easily keep the combustion engine from starting around town while comfortably keeping up with the traffic.
A ‘haptic’ accelerator pedal contributes to the intuitive functionality here, which mimics a kick-down detent marking the point of pedal travel after which the engine would be needed to provide greater acceleration. But that’s not all it does. The pedal also works in tandem with the sat-nav to encourage you to lift off and coast in plenty of time when approaching a built-up area, by issuing a short pulse of feedback direct to your right foot. For drivers not used to how best to drive for optimum economy, that’ll contribute notably to their efficiency return.
Mercedes’ claim for electric-only range is 21 miles, delivered by an 8.7kWh battery under the GLC’s boot floor. That’s less than is claimed for other similar PHEVs, but our testing suggested it’s a more accurate claim than others. On electric-only running, we covered just under nine miles using roughly 40% battery capacity. The battery takes a sliver of boot space away by raising the cargo bay floor by a couple of inches – but it leaves more than enough space for daily use.
The car’s handling is competent and controlled, with steering that is sensibly paced and weighted but generously power-assisted and muted on feedback. In both, you can feel the effect of two tones of kerb weight. Grip levels seem well matched to the car’s body control, although neither are outstanding.