Audi Q8 – engine and gearbox
Underneath you’ll find the same platform as the Cayenne, with the option of diesel, petrol or plug-in power
The Q8 shares its core platform (the Volkswagen Group’s MLB Evo) and engines with the Porsche Cayenne. You’ve a choice of V6 petrol and diesel engines, plus a V6 plug-in hybrid – and of course the V8 SQ8 and RSQ8. Air suspension and adaptive dampers come as standard, so too quattro four-wheel drive with a locking centre diff. Rear-wheel steering is offered on top-spec Vorsprung models.
The suspension consists of five-link layouts at the front and rear, with the progressive electromechanical steering rack featuring speed-sensitive power assistance (for the latest Q8, Audi has tuned the system for easier steering efforts at low speed). The smallest wheel option is 21 inches, with higher spec models coming with 22s.
The 50 TDI’s 3-litre V6 turbo diesel engine generates 282bhp and a healthy 443lb ft of torque from 1500-3000rpm. The petrol V6 in the 55 TFSI generates a higher peak power figure of 335bhp, but can’t match the diesel’s torque figure, with 369lb ft served from 1370-4500rpm. Both are linked up to an eight-speed torque converter auto and are supplemented by a 48V mild-hybrid system, which includes a lithium-ion battery that powers a belt-driven starter-generator. This allows the engine to turn off while coasting and be restarted smoothly, and boosts efficiency.
The plug-in hybrid 55 TFSI e, meanwhile, combines the petrol V6 with an electric motor and 22kWh (usable) battery pack. With 387bhp it’s the most powerful Q8 aside from the Audi Sport versions, and matches the diesel’s 443lb ft torque figure while offering up to 50 miles of pure electric running. It’s also the heaviest Q8 available, coming in at a colossal 2415kg compared to 2100kg for the standard petrol car.
