Quick Facts — S65 AMG (2006–2009)
- Engine: 6.0L M275 V12 Biturbo
- Power: 612 hp / 450 kW
- Torque: 1,000 Nm / 737 ft-lb
- 0–60 mph: 4.2 sec
- Top speed: 155 mph (limited)
- Transmission: AMG SPEEDSHIFT 5-speed automatic
- Long-wheelbase only
- Production: November 2005 – May 2009
- Most expensive W221 at launch
The Mercedes-Benz S65 AMG was the absolute top of the W221 S-Class lineup — above the S600, above the S63 AMG, above everything else Mercedes offered in this generation. It was powered by a twin-turbocharged V12, produced in long-wheelbase only, and carried a price tag that reflected both of those facts. The 2006 S65 AMG LWB launched at €211,761 in Europe — roughly 2.4 times the cost of the base S350 at the time.
This article covers the pre-facelift S65 AMG, produced from November 2005 through May 2009. The post-facelift model that followed in 2010 carried the same V12 engine in a revised body with updated electronics and equipment — that version is covered separately. If you are comparing the two generations, the engine specs are nearly identical; the differences are cosmetic and feature-based.
Basic Information
The S65 AMG uses chassis code 221.179. Unlike virtually every other W221 model, there was no standard-wheelbase option — Mercedes sold the S65 AMG exclusively in long-wheelbase configuration. That decision reflects the car’s positioning: this was not a driver’s car in the traditional sense. It was a flagship luxury performance sedan, built for a buyer who wanted the most powerful, most expensive, most exclusive version of the W221.
| Detail | Specification |
|---|---|
| Production Period | November 2005 – May 2009 |
| Make | Mercedes-AMG |
| Series | W221 S-Class |
| Model | S65 AMG (LWB only) |
| Chassis Code | 221.179 |
| Vehicle Type | 4-Door Luxury Performance Sedan |
The M275 Twin-Turbo V12 — What You’re Actually Getting
The M275 is a 6.0-litre twin-turbocharged V12 that Mercedes-AMG developed specifically for the top-tier S-Class. It produces 612 hp and 1,000 Nm of torque — numbers that were genuinely staggering for a production sedan in 2006 and that still command respect today. For context, the S600 uses a detuned version of the same engine architecture (the M275 E55), making 510 hp and 830 Nm. The S65 AMG’s extra output comes from higher boost pressure and additional AMG-specific tuning.
The torque figure is the number that defines this car’s character. 1,000 Nm arrives at just 2,000 rpm and holds through 4,000 rpm — a massive, flat band of force that makes the S65 AMG feel effortless in a way that even the S63 AMG’s naturally aspirated V8 cannot replicate. The V12 doesn’t build to power like the M156 does — it just has it, from the moment you press the throttle. Driving one, the thing that surprises most people is how quiet and composed the experience is. It does not feel fast in an aggressive way. It feels inevitable.
The trade-off is complexity. A twin-turbocharged V12 in a luxury sedan is among the most involved powertrains you can maintain. Parts are expensive, specialist knowledge matters, and skipping service intervals catches up with these cars faster than almost any other vehicle. That context is worth understanding before looking at used prices.
| Engine Data | Detail |
|---|---|
| Combustion | Four-stroke gasoline, twin-turbocharged |
| Engine Designation / Type | M275 E60 AMG / 275.982 |
| Fuel Type / System | Gasoline / Indirect Injection |
| Cylinder Arrangement | V12 |
| Bore / Stroke | 82.6 mm / 93.0 mm |
| Displacement | 5,980 cc (6.0L) |
| Compression Ratio | 9.0:1 |
Engine Power & Performance
| Performance | Figure |
|---|---|
| Horsepower | 450 kW / 612 hp @ 4,800–5,100 rpm |
| Torque | 1,000 Nm / 737 ft-lb @ 2,000–4,000 rpm |
| 0–60 mph | 4.2 seconds |
| 0–100 km/h | 4.4 seconds |
| Top Speed | 250 km/h / 155 mph (electronically limited) |
Fuel Economy
The S65 AMG drinks fuel at roughly the same rate as the S63 AMG despite the additional two cylinders — turbocharged engines at cruise are often more efficient than naturally aspirated ones of larger displacement. Where the difference shows up is in city driving with frequent acceleration, which is exactly how most S65 owners drive these cars.
| Fuel Data | Figure |
|---|---|
| Fuel Tank Capacity | 90 L / 23.8 gal |
| Recommended Fuel | Premium Unleaded (91+ octane) |
| City Consumption | 23.1 L/100km / 10.1 mpg |
| Highway Consumption | 10.0 L/100km / 23.5 mpg |
Transmission
The S65 AMG uses a 5-speed AMG SPEEDSHIFT automatic — one gear fewer than the 7-speed used in the S63 AMG. The 5-speed was chosen because the M275 V12’s torque output (1,000 Nm) exceeded what the 7G-TRONIC could reliably handle at the time. The 5-speed used here is a strengthened unit specifically rated for the V12’s output. In practice, the transmission suits the engine’s character well — the wide, flat torque band means fewer gear changes are needed, and the missing ratios are rarely missed.
| Transmission Data | Detail |
|---|---|
| Type | Automatic |
| Gearbox Designation | AMG SPEEDSHIFT 5-Speed Automatic |
| Gear Ratios | I: 3.60 II: 2.19 III: 1.41 IV: 1.00 V: 0.83 R: 3.17 |
Steering, Brakes & Tires
| Component | Specification |
|---|---|
| Steering Type | Rack-and-Pinion |
| Front Brakes / Diameter | Ventilated Disc / 390 mm |
| Rear Brakes / Diameter | Ventilated Disc / 365 mm |
| Front Wheels | 8.5J × 19 |
| Rear Wheels | 9.5J × 19 |
| Front Tires | 255/40 ZR19 |
| Rear Tires | 275/40 ZR19 |
Measurements & Weights
Because the S65 AMG was sold exclusively in long-wheelbase, there is only one set of measurements. The unladen weight increased by 20 kg after October 2006 — most likely reflecting the addition of previously optional equipment becoming standard mid-production.
| Measurement | Figure |
|---|---|
| Wheelbase | 3,165 mm / 124.6 in |
| Vehicle Length | 5,206 mm / 205.0 in |
| Vehicle Width | 1,871 mm / 73.7 in |
| Vehicle Height | 1,473 mm / 58.0 in |
| Unladen Weight | 2,250 kg / 4,960 lb (2,270 kg / 5,004 lb after October 2006) |
Pre-Facelift vs Post-Facelift S65 AMG
This article covers the pre-facelift S65 AMG. Mercedes applied a significant visual refresh to the W221 in 2009, with facelifted models going on sale in late 2009 and running through to the end of W221 production in 2013. The S65 AMG carried over with the same M275 V12 engine for the post-facelift generation — unlike the S63 AMG, which switched engines entirely at the facelift.
The main differences between the two generations of S65 AMG are cosmetic and equipment-based rather than mechanical.
| Feature | Pre-Facelift (2006–2009) | Post-Facelift (2010–2013) |
|---|---|---|
| Engine | M275 V12 biturbo — unchanged | M275 V12 biturbo — unchanged |
| Headlights | Halogen / Bi-Xenon | LED daytime running lights added |
| Tail lights | Body-color strip dividers | Full red LED units |
| Front bumper | Standard | Lower front spoiler added |
| Dashboard | Original COMAND system | Updated COMAND + revised trims |
| Front seats | Heated optional | Heated standard |
| Launch price (EUR) | €211,761 (2006) | €221,221 (2009) → €230,384 (2012) |
Note
Unlike the S63 AMG — which received an entirely new engine at the facelift — the S65 AMG carried over the M275 V12 biturbo unchanged across both generations. If you are choosing between a pre and post-facelift S65 AMG purely on mechanical grounds, the engine is not the deciding factor.
S65 AMG vs S63 AMG vs S600: How They Compare
The S65 AMG, S63 AMG, and S600 represent three different approaches to the top of the W221 lineup. The S600 is the refined choice — a V12 that prioritizes composure over outright performance. The S63 AMG is the driver’s car — a naturally aspirated V8 that rewards being worked. The S65 AMG is neither of those things in isolation. It is the most powerful, the most expensive, and the most involved to own.
Understanding where each model sits relative to the others matters when shopping used. The S65 AMG’s price premium over the S63 AMG at launch was significant — roughly €80,000 more in European markets. On the used market that gap has compressed considerably, which changes the calculus. A well-maintained S65 AMG at a used price close to an S63 AMG is a very different value proposition than it was new.
| Model | S65 AMG | S63 AMG (6.2L) | S600 |
|---|---|---|---|
| Engine | 6.0L V12 biturbo | 6.2L V8 NA | 5.5L V12 biturbo |
| Horsepower | 612 hp | 518 hp | 510 hp |
| Torque | 1,000 Nm | 630 Nm | 830 Nm |
| 0–60 mph | 4.2 sec | 4.3 sec | 4.3 sec |
| Transmission | 5-speed SPEEDSHIFT | 7-speed SPEEDSHIFT | 5-speed 5G-Tronic |
| Wheelbase options | LWB only | SWB and LWB | LWB only |
| Character | Effortless performance | Driver-focused, high-revving | Refined luxury first |
| Ownership cost | Highest | High | High |
Is the W221 S65 AMG Worth Buying?
The S65 AMG is not a car you buy casually. The M275 V12 biturbo is one of the most complex and expensive powertrains to maintain in any production saloon from this era. That is not a reason to avoid it — but it is the single most important factor in whether a used example is a good purchase or an expensive problem.
The cars I see that cause the most financial pain for their owners are not the ones with the highest mileage. They are the ones that have been maintained on a budget. A twin-turbo V12 in a flagship luxury saloon demands proper service intervals, quality oil, and attention from someone who knows the platform. Cut corners on any of those and the bill comes eventually.
A well-maintained S65 AMG with complete dealer or specialist history is a genuinely impressive used car. The performance is still significant by any modern standard, the interior quality holds up, and the long-wheelbase means it is as comfortable for rear passengers as almost anything on the road. The question is always whether the specific example in front of you has been looked after — and that takes research, not just a test drive.
| Consideration | What to Know |
|---|---|
| Service history | Non-negotiable. Full records from a Mercedes specialist or dealer — walk away from anything incomplete |
| Turbocharger condition | Listen for boost hesitation or smoke under hard acceleration — turbo replacement on a V12 is a significant job |
| Air suspension | Check all four corners sit evenly at ride height — sagging indicates failing air struts, which are not cheap |
| Transmission | Smooth shifts across all five gears — any hesitation, slipping, or hard shifts warrants further inspection |
| COMAND system | Will feel dated — factor in the cost of an aftermarket head unit if that matters to you |
| Pre vs post-facelift | Engine is identical — choose based on cosmetics, equipment, and condition rather than powertrain |
| S65 vs S63 AMG | If the used price gap is large, the S63 6.2L is the more practical performance choice — simpler to maintain |
| S65 vs S600 | Same V12 architecture, less AMG tuning — the S600 is more refined and cheaper to run if outright performance is not the priority |
⚠ Important
The S65 AMG is the most expensive W221 model to own, by a meaningful margin. If you are not in a position to absorb a significant unexpected repair bill — turbochargers, air suspension, transmission — this is not the right car for your situation right now. Come back to it when the budget is there to do it properly.
More About the Mercedes W221 S-Class
The S65 AMG sits at the very top of the W221 lineup. To understand the full range of models, engines, production figures, and pricing across the entire W221 generation, our complete W221 S-Class guide covers all of it.
If you’re comparing the S65 AMG to the other top-tier W221 models, our W221 S63 AMG article covers the pre-facelift 6.2L V8 in the same detail, and our W221 S600 guide covers the non-AMG V12.