2005 Mercedes S-Class 3.7L Petrol · KN05 DGY

The 2005 Mercedes S-Class presents a worsening maintenance trend, despite passing its most recent MOT on 2025-05-17 at 71,416 miles. After three consecutive clean tests from 2020 to 2023, the last two inspections have flagged deteriorating steering and braking components. The tester flagged slight play in the offside front inner track rod end ball joint in 2025, alongside pitted and scored rear brake discs on both sides. A year earlier, at 69,973 miles on 2024-05-11, the offside front upper suspension arm ball joint also exhibited slight play, while the rear brake discs were noted as worn. These recurring advisories indicate progressive wear in the front suspension linkage and rear braking surfaces. The presence of a non-excessive transmission oil leak in 2024 further suggests aging seals. A clean bill of health has given way to accumulating mechanical wear. The mileage pattern reflects highly irregular use over the last six years. Between 2020-11-07 and 2022-05-20, the car covered a mere 387 miles, indicating a prolonged period of dormancy that can cause flat-spotted tyres, seized brakes, and dried-out rubber seals. Usage surged dramatically on 2023-04-23 when the odometer jumped to 68,396 miles, representing an 8,447-mile spike in just eleven months. Since then, the annual mileage has settled to a steady but low 1,400 to 1,500 miles per year. This sporadic usage cycle, long dormancy followed by a sudden spike, often leads to premature degradation of consumables and suspension components due to infrequent flexing and lubrication. A physical inspection must closely evaluate the structural integrity of the front suspension and the condition of the rear braking system. The recurring advisories for play in the offside front track rod end and upper suspension arm ball joint warrant a close examination of the dust boots and joint tolerances, as failure here causes sudden steering looseness. The rear brake discs, flagged as pitted and scored in 2025, require measurement of disc thickness and inspection for heat cracking, especially given the risk of corrosion from prolonged standing. Check the transmission for residual oil leaks around the gearbox pan and output seals, as fluid seepage degrades over time. Inspect the subframes and sills for corrosion, as extended periods of inactivity in a vehicle of this age often promote rust in hidden chassis sections.