2007 MERCEDES-BENZ S600

Typical onset: 60,000-100,000 mi

Symptoms: Metallic knocking from engine bay, especially cold start, Check engine light with misfire codes (P0300-P0312 range), Metal shavings in oil during changes, Sudden loss of power or complete engine seizure

Fix: The bolted piston design allows skirts to separate from crowns, sending debris through the entire engine. Requires complete engine removal and rebuild with updated forged pistons, new rings, bearings, gaskets, timing components. 60-80 hours labor. Many owners opt for used engine swaps instead due to cost.

Estimated cost: $25,000-45,000

Typical onset: 70,000-120,000 mi

Symptoms: ABC warning light with vehicle lowered to ground, Hydraulic fluid leaks under vehicle (green fluid), Harsh ride quality or sagging corners, Pulsation pump running constantly, whining noise

Fix: ABC struts leak internally, pulsation pump fails, pressure hoses crack, and valve blocks corrode. Each strut replacement is 4-6 hours, pump is 8-10 hours. Often multiple components fail together. Fluid contamination from one failed part damages entire system.

Estimated cost: $3,500-8,000

Typical onset: 80,000-130,000 mi

Symptoms: Harsh or delayed shifts, especially 2-3 and 3-4, Transmission slipping or flaring during upshifts, Limp mode activation (stuck in 2nd or 3rd gear), Transmission fault codes (P0715, P0730, P2711)

Fix: The 722.9 (NAG2) seven-speed transmission has weak solenoids and conductor plate solder joints that crack. Requires transmission removal, disassembly, valve body replacement or rebuild, new conductor plate, fresh fluid. 18-24 hours labor.

Estimated cost: $4,500-7,500

Typical onset: 90,000-140,000 mi

Symptoms: Rattling noise from engine bay at idle (sounds like loose heat shield), Loss of boost pressure, sluggish acceleration, P0299 or P0234 boost control codes, Excessive blue smoke on startup if seals fail

Fix: Wastegate actuator arms break or seize on BorgWarner turbos. Often just the rattle without performance loss initially. Turbo replacement requires engine work to access, coolant drain, oil feed lines. 12-16 hours per side. Both typically need doing within 20k miles of each other.

Estimated cost: $3,800-6,500

Typical onset: 60,000-110,000 mi

Symptoms: No-start condition or extended cranking, Rough idle with timing rattle from valve covers, P0016, P0017 cam/crank correlation codes, Check engine light with reduced power

Fix: Crank sensors fail causing no-start. Camshaft adjusters (solenoids and gears) wear causing timing issues. Crank sensor is 2-3 hours, cam adjusters require valve cover removal on each bank, 8-12 hours total for both sides.

Estimated cost: $1,800-3,500

Typical onset: 70,000-120,000 mi

Symptoms: Fuel pump whining noise from rear of vehicle, Hard starting or no-start after sitting, Hesitation or stumbling under acceleration, P0087 fuel pressure too low code

Fix: Both in-tank fuel pumps fail, fuel filters clog (under rear seat access), and fuel pressure regulator leaks. Tank must be dropped for pump replacement. 6-8 hours labor for pumps, 2 hours for filters. V12 requires high-pressure pumps and has two filters.

Estimated cost: $2,200-3,800

Typical onset: 50,000-90,000 mi

Symptoms: Excessive vibration at idle in Drive, Clunking when shifting from Park to Drive/Reverse, Engine rocking visible when revving in Park, Harsh throttle tip-in response

Fix: Hydraulic engine mounts and transmission mounts fail frequently due to V12 weight and torque. Four engine mounts plus trans mount all need replacing as a set. 6-8 hours labor total. Subframe may need dropping for access.

Estimated cost: $1,800-2,800