Sedan or wagon? If you want reliability and ease of maintainance get an 04-05 RWD E320. M112/722.6 is by far the most reliable drivetrain they put into the 211. Avoid 03s. 722.9 found in E500/E350/E550 is not maintance friendly like the 722.6. There's no fill tube and the TCM is built into the conductor plate and coded to the car. The M272 and M273 intake manifold is failure prone and can sometimes send it's components into the intake. Avoid anything with airmatic. It is very expensive every time anything fails. That includes shocks, airbags and sensor.

SBC brakes on 03-06 cars are covered under a 25 year unlimited mileage extended warranty. The fuel tank on all non PZEV 211s is covered under a 15 year unlimited mileage warranty.

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CENSORED due to not family friendly words