Air Suspension Failure (bags, compressor, valve block)
high- Typically appears
- 50–100k mi
- Estimated repair
- $2,500 – $8,000
2012 Bentley
MulsanneSedan
Sedan
The 2012 Bentley Mulsanne is the hand-built flagship sedan from Crewe, England — a full-size ultra-luxury car powered by a twin-turbocharged 6.75L V8 that traces its lineage back to the 1950s yet was thoroughly re-engineered for this generation. It sits at the very top of the luxury sedan market alongside the Rolls-Royce Ghost, and nearly everything inside — from the hand-stitched hides to the machined aluminum controls — is assembled by craftspeople in small batches. Production numbers are extremely low; fewer than a few hundred were sold in the U.S. each year. Behind the prestige is a mechanically complex vehicle that demands specialist attention. The engine management, air suspension, and body electronics systems require factory-level or Bentley-trained diagnostic equipment (ODIS or equivalent) to service properly. Parts supply is limited and expensive, and labor rates at qualified shops reflect the rarity and complexity of the platform. Owning a Mulsanne in Lake Geneva means budgeting seriously for maintenance, storing it appropriately over winter (road salt is extremely harsh on the aluminum-intensive body and air suspension components), and building a relationship with either the nearest Bentley dealer or a well-equipped independent European specialist. This is not a vehicle to defer maintenance on.
Reliability
2/5
Verified data
Specs shown for Mulsanne — the most common configuration.
Other trims may vary in engine, drivetrain, or fuel economy. Sign in to see your vehicle's exact specs.
Engine
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Drivetrain
RWD
Fuel
Premium gasoline
MPG
11 city / 18 hwy / 13 combined
Seats
—
Doors
—
Body
Midsize Cars
Overview
AI-curatedThe 2012 Bentley Mulsanne is the hand-built flagship sedan from Crewe, England — a full-size ultra-luxury car powered by a twin-turbocharged 6.75L V8 that traces its lineage back to the 1950s yet was thoroughly re-engineered for this generation. It sits at the very top of the luxury sedan market alongside the Rolls-Royce Ghost, and nearly everything inside — from the hand-stitched hides to the machined aluminum controls — is assembled by craftspeople in small batches. Production numbers are extremely low; fewer than a few hundred were sold in the U.S. each year. Behind the prestige is a mechanically complex vehicle that demands specialist attention. The engine management, air suspension, and body electronics systems require factory-level or Bentley-trained diagnostic equipment (ODIS or equivalent) to service properly. Parts supply is limited and expensive, and labor rates at qualified shops reflect the rarity and complexity of the platform. Owning a Mulsanne in Lake Geneva means budgeting seriously for maintenance, storing it appropriately over winter (road salt is extremely harsh on the aluminum-intensive body and air suspension components), and building a relationship with either the nearest Bentley dealer or a well-equipped independent European specialist. This is not a vehicle to defer maintenance on.
Known for
- Hand-built, coach-built quality interior with bespoke personalization options
- Twin-turbocharged 6.75L V8 — enormous torque from very low RPM
- Extraordinarily smooth, wafting ride character on air suspension
- One of the highest MSRPs and ownership costs in the passenger-car segment
- Low production volumes and long parts lead times
Best for
- Long-distance highway cruising in maximum comfort
- Chauffeur-driven or owner-driven grand touring
- Collectors and enthusiasts who can absorb premium ownership costs
- Those who already have a relationship with a Bentley-trained technician
Watch for
- Air suspension failures — expensive and not uncommon as cars age
- Electrical and body control module issues requiring proprietary diagnostic tools
- Extremely high parts costs and long lead times from the UK
- Road salt accelerating corrosion on air suspension bags, lines, and underbody
- Deferred maintenance — costs compound quickly on this platform
Common issues by mileage
6 knownVVT / Camshaft Position Timing Faults (oil sludge or solenoid wear)
medium- Typically appears
- 40–80k mi
- Estimated repair
- $800 – $3,500
Turbocharger Bypass Valve Failure
medium- Typically appears
- 60–100k mi
- Estimated repair
- $1,200 – $4,000
Oxygen / A/F Sensor Heater Circuit Faults
medium- Typically appears
- 50–90k mi
- Estimated repair
- $600 – $2,000
CAN Bus / Module Communication Loss (body, chassis, network)
medium- Typically appears
- 60–120k mi
- Estimated repair
- $1,000 – $5,000
Body Control / Airbag System Faults
low- Typically appears
- 70–120k mi
- Estimated repair
- $1,500 – $6,000
Maintenance schedule
- 1 Every 10,000 miles or 12 months — whichever comes first Engine oil and filter change
The twin-turbo V8's VVT system is oil-pressure sensitive. Using the wrong viscosity or extending intervals leads to sludge in the camshaft solenoid passages — exactly the condition behind P0012/P0015/P0022/P0025 codes. Use only Bentley-approved full-synthetic. Drain plug torque spec is 30 ft-lb; do not overtighten. Proprietary reset via ODIS or compatible software required after service.
- 2 Every 20,000 miles or annually Air suspension inspection (bags, compressor, valve block, lines)
Wisconsin road salt accelerates corrosion on the metal air lines and valve block fittings. Inspect for cracked bags and slow-leak symptoms (nose or tail sitting low overnight). Catching a single bag early is far cheaper than replacing the compressor after it burns out trying to compensate.
- 3 Every 40,000–50,000 miles Transmission fluid change (ZF 8-speed)
ZF rates this as 'lifetime' fluid, but independent specialists consistently find degraded fluid in high-mileage examples. Fresh fluid noticeably improves shift quality and protects valve body components.
- 4 Every 30,000 miles Spark plug replacement
The twin-turbo environment accelerates plug wear. Worn plugs stress ignition coils and can cause misfires that are expensive to diagnose on this platform. Do all 8 at once — partial plug changes are false economy here.
- 5 Every 4 years or 60,000 miles Coolant system inspection and flush
Degraded coolant accelerates corrosion in the aluminum engine block and cooling passages. Wisconsin's freeze-thaw cycles make the 50/50 mix ratio non-negotiable.
- 6 Every 2 years regardless of mileage Brake fluid flush
Brake fluid is hygroscopic. With the Mulsanne's weight (nearly 3 tons), maintaining full braking performance is critical. Moisture-contaminated fluid lowers boiling point significantly.
- 7 Every fall before winter storage or active winter use Battery load test and charging system inspection
The Mulsanne's extensive electronics draw heavily on the battery even when parked. A marginal battery in sub-zero Wisconsin temps will fail and can trigger a cascade of module fault codes (U0100–U0104) as voltage drops during cranking.
- 8 After every significant road-salt exposure; full inspection each spring Underbody wash and corrosion inspection
The air suspension components, brake lines, and exhaust systems on these cars are not cheap to replace. Salt trapped in body seams and underneath the rear wheel arches is a known problem area. Rinse thoroughly — including the undercarriage — after winter driving.
Always defer to the manufacturer's service manual for warranty-mandated intervals.
Cost of ownership
Annual maintenance
$4,000 – $12,000
Fuel
Premium 91+ octane required. At 13 MPG combined and ~12,000 miles/year, expect $3,000–$4,500/year in fuel depending on pump prices.
Insurance
Typically $3,000–$6,000/year for a vehicle in this value range in Wisconsin; highly dependent on garaging, annual mileage, and driver profile. Agreed-value coverage is strongly recommended.
The Mulsanne is one of the most expensive vehicles to own outside of exotic supercars. Annual maintenance at an independent European specialist runs $4,000–$12,000 in routine years; a single air suspension overhaul or major electrical repair can add $5,000–$15,000 on top of that. Parts are imported and have long lead times. Fuel is a secondary cost compared to maintenance. Budget conservatively, store it properly over winter, and never defer scheduled service.
Seasonal care
Lake Geneva, WI Winter
- Do not drive this vehicle on heavily salted roads if avoidable — the air suspension components, aluminum body panels, and underbody are highly vulnerable to salt corrosion. Consider winter storage.
- If driven in winter, rinse the full undercarriage within 24 hours of salt exposure, paying special attention to the rear suspension and air line routing.
- Load-test the battery every fall. The heavy electronics load and sub-zero cranking demands will kill a marginal battery quickly. Keep a quality trickle charger on the vehicle during storage.
- Use full-strength washer fluid rated to at least -20°F. The large windshield and powered washer jets can crack if fluid freezes in the lines.
- Check tire pressure monthly — pressures drop roughly 1 PSI per 10°F. The Mulsanne's weight makes underinflation especially punishing on sidewalls and suspension.
- If storing for winter, treat fuel with a stabilizer, disconnect or maintain the battery with a smart charger, and store indoors or under a breathable cover away from freeze-thaw extremes.
Summer
- Inspect the A/C system each spring — the large cabin takes significant cooling capacity and a marginally charged system will struggle on hot Wisconsin days. Address refrigerant and cabin filter proactively.
- Check and correct tire pressures in the morning before heat builds — hot pavement and the vehicle's weight are hard on tires that started the day low.
- Inspect air suspension bags for cracking or dry-rot in the heat; UV and ozone exposure age rubber components faster in summer.
- The large 6.75L engine produces substantial heat at idle. Ensure the cooling system is in top condition — coolant mix, hoses, and thermostat — before summer heat arrives.
- Inspect the condition of all rubber seals around the panoramic roof and door frames annually; UV degradation leads to leaks that damage the bespoke interior quickly.
Comparable vehicles
2012 Rolls-Royce
Ghost
Direct segment rival — similarly hand-built British ultra-luxury sedan, BMW-based platform vs. Bentley's VW Group underpinnings. The Ghost is slightly more driver-focused; ownership costs and parts challenges are comparable.
2012 Mercedes-Benz
S600
V12-powered flagship S-Class occupies the same ultra-luxury sedan space at a somewhat lower price point. Better parts availability and more dealer support, but lacks the handcrafted exclusivity of the Mulsanne.
No catalog match
2012 Maybach
57
Mercedes-Maybach's ultra-long-wheelbase flagship matched the Mulsanne's mission of chauffeur-grade luxury. Production ended in 2012, making parts increasingly difficult to source — similar ownership challenges.
2012 Aston Martin
Rapide
Four-door gran turismo in the same price bracket targeting buyers who want exclusivity and performance over pure luxury. Lower weight, more driver engagement, but similarly demanding in terms of service and parts costs.