Verdict
B
← Audi S8 · 2013-present · D4/D5
Audi S8 D4 / D5 Twin-Turbo V8
4.0 TT V8 era. 520-605 hp depending on variant. Quietly extraordinary luxury sport sedan.
BHP
520-605 bhp
0–60
3.6 s
Top speed
155 mph
MPG
18.0 mpg
Used
$30,000-$95,000
The D4 (2013-2017) ditched the V10 for a 4.0-litre twin-turbo V8 making 520 hp and 481 lb-ft — significantly more power than the V10 it replaced, with vastly better fuel economy. Eight-speed Tiptronic automatic, quattro AWD. The S8 Plus (2016-2017 only) raised the engine to 605 hp and 553 lb-ft, dropping the 0-60 to 3.6 seconds — faster than any M-car of its era. The D5 (2020-present) uses the same 4.0 TT V8 platform retuned to 563 hp with 48-volt mild-hybrid integration. Predictive Active Suspension on the D5 reads the road ahead via cameras and pre-adjusts the air springs corner-by-corner — genuinely revolutionary tech. The S8 has consistently been quicker than the obvious BMW and Mercedes-AMG rivals, but sells in tiny numbers. The S8 Plus is the cult collector pick of the modern era.
Strengths
- S8 Plus (2016-2017) at 605 hp / 3.6-second 0-60 is faster than its M-car rivals
- Predictive Active Suspension on D5 is genuinely advanced
- Twin-turbo V8 + 48V mild hybrid is impressively efficient for the segment
- Sleeper styling — looks subtle for the engine inside
- Quattro AWD makes it all-weather usable
Weaknesses
- Sells in tiny volumes (low used supply)
- Heavy at 4,800+ lb
- MMI haptic touchscreens (D5) polarise
- Carbon build-up still an issue on direct-injection V8
- Air suspension service costs
Notable tech
- 4.0L twin-turbo V8 (520-605 hp depending on variant)
- Predictive Active Suspension (D5)
- 48-volt mild-hybrid system (D5)
- Bang & Olufsen 23-speaker audio (top trim)
- Quattro AWD with Sport differential
- S8 Plus rear-axle steering
Common issues
- Timing chain tensioner concerns (4.0 TT V8)
- Air suspension air-spring leaks
- Carbon build-up on intake valves
- MMI haptic-screen complaints (D5)
- Front control arm bushings wear
Used-market budget
$48,000
D4 standard cars $30-50k. D4 S8 Plus (cult) $55-75k. D5 (2020-2024) $65-95k. Predictive Active Suspension on D5 service is expensive but rarely needed.