The 2008 DB9's 6.0L V12 is a hand-built marvel that demands respect and deep pockets. When maintained properly it's phenomenal, but deferred service and heat management issues lead to catastrophic engine failures that can exceed the car's remaining value.
Catastrophic Engine Bearing Failure
Occasional · high severityTypical onset: 60,000-90,000 mi
Symptoms: metallic knocking from lower engine, sudden oil pressure drop, metal shavings in oil filter, check engine light with low oil pressure codes
Fix: Main and rod bearings fail due to inadequate oiling during heat soak and extended oil change intervals. Requires full engine-out teardown, crankshaft inspection/machining, new bearings throughout. 80-120 labor hours depending on damage extent. Many shops recommend short block replacement instead of rebuild due to labor economics.
Estimated cost: $25,000-45,000
Transmission Oil Cooler Failure and Mounts
Common · medium severityTypical onset: 50,000-80,000 mi
Symptoms: transmission overheating warnings, harsh shifting when hot, visible transmission fluid leaks at cooler lines, clunking on acceleration/deceleration from worn mounts
Fix: The ZF 6-speed auto's external oil cooler develops leaks at crimp points and hose connections. Mounts fail from engine torque. Cooler replacement is 8-12 hours including fluid service. Mounts add 6-8 hours due to exhaust removal requirements.
Estimated cost: $2,800-4,500
Coil Pack and Spark Plug Failures
Common · medium severityTypical onset: 40,000-70,000 mi
Symptoms: misfires under load, rough idle, flashing check engine light, bank-specific misfire codes, reduced power mode
Fix: All 12 coil packs crack internally from heat cycling in the valley. Spark plugs foul from carbon buildup. Replace all 12 coils and plugs as a set preventatively. 6-8 hours labor due to intake plenum removal and tight access.
Estimated cost: $2,200-3,200
Front Lower Control Arm Bushings and Ball Joints
Common · medium severityTypical onset: 45,000-75,000 mi
Symptoms: clunking over bumps, wandering steering feel, uneven tire wear on inside edges, alignment won't hold specs
Fix: Aluminum arms use pressed bushings that deteriorate from road salt and stress. Ball joints wear due to weight. Arms are replaced as complete assemblies—bushings aren't serviceable separately. 8-10 hours for both sides with alignment. Subject of NHTSA recall for specific production batches.
Estimated cost: $3,500-5,000
Fuel System Clogging and Filter Neglect
Occasional · high severityTypical onset: varies with maintenance
Symptoms: extended cranking before start, loss of power above 4000 RPM, lean fuel trim codes, hesitation under acceleration
Fix: In-tank fuel filters rarely get changed per 20k service schedule. Clogged filters starve the high-pressure pump, causing lean conditions that damage cats and risk valve damage. Filter replacement requires tank drop. 6-8 hours labor.
Estimated cost: $1,200-1,800
Battery Cable Corrosion and Electrical Gremlins
Common · low severitySymptoms: intermittent no-start, multiple module fault codes, battery light flickering, interior electronics resetting, parasitic battery drain
Fix: Battery cables corrode at crimps in engine bay heat. Poor grounds cause cascading module faults. Subject to recall but corrosion continues. Clean/replace main power and ground cables, apply dielectric grease. 3-5 hours to chase all connection points properly.
Estimated cost: $800-1,500
Accelerator Pedal Position Sensor Failure
Occasional · medium severitySymptoms: throttle cuts out momentarily, limp mode activation, erratic idle speed, accelerator pedal position codes
Fix: Pedal assembly sensor develops intermittent open circuits. Entire pedal assembly requires replacement—sensor isn't sold separately. Subject to recall but failures continue post-fix. 2-3 hours labor.
Estimated cost: $900-1,400
Only buy if you have a $10k annual maintenance fund and accept that a missed oil change can cost more than the car's worth—spectacular when healthy, financially devastating when neglected.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.