2007 MERCEDES-BENZ SL600 R230

Typical onset: 50,000-90,000 mi

Symptoms: Rough idle and misfires, especially when cold, Excessive oil consumption (quart per 500-1000 miles), White/blue smoke on startup, Multiple misfire codes across various cylinders, Low compression readings on bore scope inspection

Fix: The M275 cylinder bores use a Silitec plating that deteriorates prematurely, allowing piston ring blow-by. Only real fix is complete engine rebuild with re-sleeved or re-plated cylinders, new pistons, rings, bearings. 60-80 hours labor. Some owners opt for used/reman long-block swap at 40-50 hours.

Estimated cost: $18,000-35,000

Typical onset: 70,000-120,000 mi

Symptoms: ABC warning light with "Vehicle rising" or "Drive carefully" message, Car drops to bump stops overnight or while parked, Hydraulic fluid leaks at struts or lines, Rough ride quality, loss of self-leveling, Pulsation pump noise or whine from front of engine

Fix: ABC struts leak internally, pulsation pump fails, pressure hoses crack. Each front strut runs 8-10 hours, rears 6-8 hours. Pump replacement 4-6 hours. Accumulator spheres (set of 3) fail around same mileage, add 3-4 hours. Most cars need multiple components by 100k.

Estimated cost: $3,500-9,000

Typical onset: 60,000-100,000 mi

Symptoms: Transmission fluid leaking from cooler lines at radiator, Harsh shifts or delayed engagement when cold, Clunking on acceleration/deceleration from worn mounts, Pink fluid visible under car after parking

Fix: The 722.6 transmission cooler lines corrode where they connect to the main radiator. Cooler replacement involves partial radiator removal, 4-5 hours. Transmission mount (13mm aluminum sandwich design) cracks and sags, 2-3 hours to replace. Often done together.

Estimated cost: $1,200-2,500

Typical onset: 80,000-130,000 mi

Symptoms: Limp mode with underboost codes (P0045, P0048), Lack of power above 3000 RPM, Rattling from turbos on cold start, Oil smoke under hard acceleration if feed lines leak

Fix: Vacuum-operated wastegate actuators stick or diaphragm tears. Actuators can sometimes be replaced separately (6-8 hours per side), but often requires turbo removal. Oil feed lines crack at fittings. Full turbo replacement runs 16-20 hours labor due to V12 packaging.

Estimated cost: $2,500-8,000

Symptoms: Keyless entry stops working, car won't recognize key fob proximity, Doors won't lock/unlock from exterior handles, Central locking works from interior but not exterior, Hissing sound from door panels, Trunk won't open via soft-close button

Fix: Keyless Go control module behind dash fails (3-4 hours to access and replace). Vacuum pump for door locks and trunk soft-close deteriorates, lines crack. Pump replacement 2-3 hours, individual door lock actuators 1-2 hours each. Not critical but annoying on a $150k car.

Estimated cost: $800-2,200

Typical onset: 100,000-150,000 mi

Symptoms: Red brake warning light with message "Brake System Malfunction, Visit Workshop", Increased brake pedal effort, loss of power assist, ABS/ESP lights illuminated, Whining or buzzing from brake pump under hood

Fix: SBC system was replaced under extended warranty by Mercedes through 2015, but these cars are now beyond that. Pump/accumulator unit fails, requires complete SBC unit replacement, 5-7 hours labor. Mercedes discontinued support; aftermarket reman units available. Critical safety item.

Estimated cost: $2,800-4,500