2004 MERCEDES-BENZ SL

Typical onset: 60,000-120,000 mi

Symptoms: Sudden rattling or grinding noise from deep in the engine, Metal shavings in oil during oil changes, Check engine light with cam/crank correlation codes, Complete engine seizure if gear teeth break and circulate through oil system

Fix: The balance shaft gear bolts back out or the gear itself fails, sending metal through the entire engine. Requires complete engine rebuild or replacement. 25-35 hours labor for short block swap, 40+ hours for in-chassis rebuild with machine work.

Estimated cost: $8,000-15,000

Typical onset: 70,000-100,000 mi

Symptoms: ABC warning light with vehicle sagging on one or more corners, Hydraulic fluid leaks at strut seals or pump connections, Rough ride quality or clunking over bumps, Car sits very low when parked overnight

Fix: ABC struts leak internally, pump fails, or accumulator spheres rupture. Each strut replacement is 3-4 hours, pump is 6-8 hours. Fluid is expensive special Mercedes hydraulic oil. Often multiple components fail together.

Estimated cost: $2,500-8,000

Typical onset: 80,000-130,000 mi

Symptoms: Harsh or delayed shifts, especially 2-3 and 3-4, Limp mode with transmission fault codes, Slipping between gears or failure to engage, Intermittent no-start due to conductor plate cracks

Fix: The 13-pin conductor plate develops cracks, valve body solenoids fail. Requires transmission pan drop, valve body removal, and replacement of conductor plate and often the valve body itself. 8-12 hours labor.

Estimated cost: $1,800-3,500

Typical onset: 60,000-110,000 mi

Symptoms: Transmission fluid mixing with coolant (strawberry milkshake in expansion tank), Low transmission fluid level with no visible external leaks, Overheating transmission or engine, Pink residue in coolant reservoir

Fix: Internal cooler in radiator fails, allowing cross-contamination. Requires radiator replacement and complete transmission fluid flush. If caught late, transmission rebuild needed. 4-6 hours for radiator and flush.

Estimated cost: $1,200-2,500

Typical onset: Not mileage-dependent, age-related

Symptoms: Red 'STOP Vehicle' warning with brake system fault, Whining or grinding from brake pump under hood, Extremely hard brake pedal or total brake failure, ABS and ESP warning lights illuminated

Fix: The electrohydraulic brake system pump fails due to age and moisture. Mercedes discontinued support. Aftermarket rebuilds available. 3-4 hours labor but parts are scarce and expensive.

Estimated cost: $2,000-4,500

Typical onset: Any age, wear-related

Symptoms: Top moves slowly or stops mid-cycle, Hydraulic fluid puddles in trunk or on driveway, Top will not latch properly, Hydraulic pump runs continuously

Fix: Hydraulic cylinders, lines, and pump develop leaks. Requires identifying specific leak points and replacing cylinders or lines. Labor varies widely: 2-8 hours depending on which component. Top removal often required.

Estimated cost: $800-2,500

Typical onset: 70,000-110,000 mi

Symptoms: Compressor runs constantly, Vehicle sags at one corner or entire rear end, Suspension warning light on dash, Compressor noise but no air pressure building

Fix: Air struts develop leaks at bellows, compressor fails from overwork. Each strut is 2-3 hours, compressor is 3-4 hours. Often need multiple struts and compressor relay.

Estimated cost: $1,500-4,000