2022 Mercedes-Benz S 400 L AMG Line Prem + D 4M A 2.9L Diesel · LH22 AAX

The 2022 Mercedes-Benz S 400 L AMG Line Premium D 4M AT has achieved a flawless MOT test record, with both recent inspections—on 2025-05-19 and 2026-06-13—yielding a clean pass with no recorded defects or advisories. This consistency in test outcomes suggests a stable maintenance history, indicating that the vehicle has been subject to regular servicing and that any potential underlying issues have either been addressed promptly or are currently within acceptable operational limits. The absence of recurring failures or advisories, particularly in high-wear areas such as brakes, suspension, or exhaust emissions, further reinforces confidence in the vehicle’s current roadworthiness. However, the low recorded mileage of 17,500 miles over four years—approximately 4,375 miles annually—raises questions about usage patterns that warrant closer scrutiny. Such a mileage rate could imply either minimal operational demand, prolonged periods of inactivity, or potentially excessive standing, all of which can accelerate wear on critical components like brakes, suspension, and fluids due to corrosion, binding, or degradation from stagnation. The annual mileage figure of around 4,375 miles is notably low for a vehicle of this age and performance class, particularly given the S-Class’s reputation for higher usage rates in both commercial and personal contexts. For a 4-year-old car with 17,500 miles, this suggests either a very light workload or significant periods of non-use, which can lead to specific concerns. Standing vehicles are particularly prone to issues such as brake disc corrosion or rusting, where moisture and lack of movement cause calipers to bind or discs to seize, leading to uneven braking performance or even failure. Suspension components, including coil springs, shock absorbers, and suspension bushes, may also suffer from stiffness or premature wear due to reduced dynamic loading, potentially resulting in clunking noises or reduced ride quality. Additionally, fluids such as brake fluid, differential fluid, and engine coolant can degrade over time when not circulated, risking leaks, reduced effectiveness, or catastrophic failure if not replaced. As a prospective buyer, the most critical physical checks for this vehicle should focus on the effects of low mileage and potential standing-related wear. Begin with a thorough inspection of the brakes, paying particular attention to the front and rear discs for signs of corrosion, pitting, or binding. Listen for any unusual grinding or squeaking noises during braking, which could indicate caliper binding or worn brake pads. The brake fluid reservoir should be checked for leaks and fluid level, with a visual inspection for contamination or discolouration, as this may signal fluid degradation. Next, examine the suspension system for any stiffness or play in the coil springs and shock absorbers, testing for excessive clunking or uneven ride quality when driving over bumps. Inspect the suspension bushings for dryness or cracks, which could lead to premature failure and poor handling. For fluids and components that benefit from time-based servicing, prioritise checking the engine coolant, differential fluid, and brake fluid for their age and condition. Given the vehicle’s age and low mileage, the coolant should be replaced if it has been in service for more than five years, as it can degrade and corrode internal components. The differential fluid should also be assessed, with a replacement recommended if it has not been changed in the last two years, as it can thicken and lose lubricating properties. The 12V battery should be tested for voltage and overall health, particularly if the vehicle has been left unused for extended periods, as standing batteries can suffer from sulphation or corrosion. Finally, verify the service book for any scheduled maintenance, such as timing belt replacement or oil changes, which may have been deferred due to low usage. A comprehensive test drive should include checks for exhaust emissions compliance, fluid leaks, and any unusual noises or vibrations, ensuring the vehicle remains in a safe and reliable condition for continued operation.