The (B8.5/8.5T or Facelift) Audi S5 Coupé uses the 3.0 L Supercharged V6 TFSI engine producing 245 kW, previously used in the S5 Cabriolet and S4 Sedan/Avant since the 2010 model year. The other major change under the bonnet is the introduction of stop-start technology for better fuel efficiency. Audi claims an average fuel economy of 8.9 litres/100 km (compared to the current 12.6 litres/100 km in the V8 coupe and 10.7 litres/100 km in the Cabriolet). In 2017, Audi replaced the supercharged 333 HP engine with a single turbocharged 183 cu in, 2995 cc, 354 HP engine, an increase of 21 HP from the supercharged model. Although more powerful at low RPM, Audi made a decision to replace the supercharger with a turbocharger based on European driver's preference for smaller, more efficient, yet powerful engines, a market which Mercedes and BMW have always lead.

As part of the mid-generational refresh, the S5 undergoes some major front-end changes, including a complete redesign of the headlights – this means new LED DRL's, a brand-new grille loosely based on the 2012 Audi A6 grille and new fog lamps. Audi has also introduced a new rear diffuser that appears to be more cosmetic than the one found on previous models and updated LED tail light design.

Inside, the S5 receives some new features. Dials in the center console get the chrome treatment along with the edges of the buttons for the windows, 4 Audi MMI control buttons and Audi's 3G+ MMI which has a slightly refreshed interface and now features Google Earth maps. Audi has brought the shift knob from the RS5 to the S5. There is a shift from having four buttons down each side of the console, to just two with the addition of a Menu and Car buttons below the MMI control dial (Audi has removed the skip forward / backward buttons that previously occupied the space on either side of the back button). Lastly, a flat-bottom steering wheel style will have a new circular airbag cover as well as piano black trim.