The Aero's engine is essentially the same as that used in the 9-3 Viggen model.

Both 9-5 Aero and Viggen get an upgraded version of the original 2.3 high-pressure turbo with stronger pistons and connecting rodsA new emission control system uses twin catalytic converters to surpass world-wide emission standards In manual transmission models, the engine provides a 20-second over boost facility that increases torque from the specified maximum of 350Nm to 370Nm Automatic version of the 9-5 Aero reduces maximum torque to 330Nm Aero suspension has been lowered 10mm and has firmer springs and shock absorbers than standard 9-5 Upgraded brake system incorporates larger 308mm ventilated front discs A higher performance pad lining material is used Heated and ventilated front seats are standard 17-inch wheels with 225/45R17 Michelin Pilot HX tyres are standard Aero Estate has a new front spoiler, side skirts and a unique rear bumper apron Driver, passenger and front side airbags are standard The Aero features Saab's active front head restraints. In a crash, the headrest moves forward and upwards to help reduce whiplash injuries Isolated front and rear sub-frames improve ride refinement Aero's night panel display closes down all dash lights and instrumentation except the speedometer to reduce distractions when driving at night Optional slide-out rear floor is capable of carrying 200kg Rear cargo tracks in Estate are strong enough that one hook alone could support the weight of the car Estate was designed concurrently with sedan 9-5 Replaceable upper rear bumper panel should be a boon at trade-in time