2006 — 2014
5.5L (M275) - CL 600 V12 Bi-Turbo
Petrol
Observe the ABC (Active Body Control) system by navigating some roundabouts. Check for any sagging or uneven ride height when parked, as the hydraulic struts and pump are complex components in these flagship cruisers.
Gently accelerate and decelerate to feel for any hesitation or 'hunting' in the 5-speed transmission. The high torque of the V12 can put extra strain on the drivetrain, so smooth gear changes are a positive sign of well-maintained fluid.
While the engine is at operating temperature, perform a cold-start check if possible to listen for any ticking or rattling from the valve train. It is common to ensure the M275 engine has had consistent oil changes, as these engines are sensitive to oil quality.
Verify the electronic amenities like the soft-close doors and COMAND infotainment system. These luxury features are quite advanced, and checking that every button operates as intended helps gauge the car's overall electronic health.
Consider a full cooling system refresh, as the heat generated by the Bi-Turbo V12 can be demanding on hoses and coolant seals.
Typically a time to inspect the engine mounts and transmission mounts, which can soften over time due to the massive torque output.
Recommended to have the ignition transformer packs and spark plugs assessed, as these are vital for maintaining the smooth performance expected of a V12.
Stick to a strict engine oil and filter service interval, ideally every 7,500km to 10,000km, to keep those twin turbos happy.
Regularly inspect the ABC hydraulic fluid levels and condition; keeping this fluid clean helps extend the life of the entire suspension system.
Keep an eye on the coolant condition and ensure the radiator and intercooler cooling circuits are free of debris for optimal performance.
Periodically check the health of the auxiliary battery, which supports the vehicle's extensive electronic systems.
Use high-quality premium fuel to ensure the engine management system operates at its most efficient.
Estimated repair costs if issues arise
Given the age of these vehicles, the hydraulic suspension components may eventually require refurbishment or replacement. It is wise to set aside some funds in your future budget to ensure this signature ride quality remains as smooth as the day it left the factory.
The M275 V12 utilizes specialized ignition packs. Depending on the car's service history, you might eventually need to budget for these to prevent potential misfires and ensure the engine continues to run with its characteristic silkiness.
The heat cycles under the bonnet can lead to the hardening of rubber seals or lines. It is helpful to plan for a proactive inspection and potential replacement of these lines to prevent any minor leaks as part of your long-term ownership plan.
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Disclaimer: This report is generated with the assistance of AI analysis based on verified automotive data. While we strive for 100% accuracy, enthusiasts should always conduct physical inspections and consult service records. View Full Disclaimer