Verdict
B
Performance Saloon · Germany · 1999-Present
Audi S6
Audi S6 — spec data and generation history.
Years
1999-Present
Generations
4
Segment
Performance Saloon
S-badged version of the A6. Saloon and Avant (estate) bodies. C5 (1999–2004) — 4.2 V8, 335 bhp. C6 (2006–2011) — 5.2 V10 (Lamborghini Gallardo-derived), 429 bhp. C7 (2012–2018) — 4.0 TFSI twin-turbo V8, 444 bhp. C8 (2019-Present) — 3.0 TDI mild-hybrid V6 diesel in Europe (348 bhp), or 2.9 TFSI V6 petrol in some markets. UK got the diesel. Always quattro. The C8 diesel is the unusual European choice — most rivals went pure petrol, Audi went biturbo diesel for the WLTP era.
Generations
Click any generation for the full deep dive
1999-2004
C5
→
4.2 V8 quattro — 335 bhp, 0-62 in 6.7s.
Verdict
C
BHP
335
0–60
6.7 s
Top
155 mph
MPG
17 mpg
Used
$3,800-$13,000
- + 4.2 V8 soundtrack
- + Saloon + Avant
- − Big thirst
- − Heavy
2006-2011
C6
→
5.2 V10 quattro — 429 bhp, 0-62 in 5.1s.
Verdict
B
BHP
429
0–60
5.1 s
Top
155 mph
MPG
17 mpg
Used
$10,000-$25,000
- + 5.2 V10 — Lamborghini Gallardo-derived
- + Sleeper saloon look
- − Eye-watering V10 parts costs
- − Heavy
2012-2018
C7
→
4.0 TFSI quattro — 444 bhp, 0-62 in 4.4s.
Verdict
B
BHP
444
0–60
4.4 s
Top
155 mph
MPG
23 mpg
Used
$18,000-$41,000
- + 4.0 TFSI biturbo V8
- + 7-speed S-Tronic dual clutch
- − Cylinder-on-demand stutter
- − Carbon build-up known issue
2019-Present
C8
→
3.0 TDI MHEV quattro — 348 bhp, 0-62 in 5.0s.
Verdict
B
BHP
348
0–60
5.0 s
Top
155 mph
MPG
30 mpg
Used
$36,000-$79,000
- + Diesel torque (700 Nm)
- + Mild hybrid efficiency
- − Diesel — fewer buyers want it now
- − Less exciting than V8/V10 era
Known issues by generation
Common faults reported on each generation — useful when shopping the used market.
1999-2004 · C5
- 4.2 V8 timing chain (front-mounted)
- Cam tensioner failures
- Air mass meter wear
2006-2011 · C6
- 5.2 V10 — bulletproof if oiled, eye-watering parts costs
- Carbon build-up on intake valves
- Air suspension compressor wear
2012-2018 · C7
- 4.0 TFSI carbon build-up
- 7-speed S-Tronic mechatronic faults
- Cylinder-on-demand stutter complaints
2019-Present · C8
- 3.0 TDI MHEV AdBlue dosing
- EA Eight mechatronic on early
- MMI freezes pre-2022