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Try to stick to facelift cars from 2003 onwards, as there were a large number of improvements, which made it more reliable and a little more modern in appearance. You can spot a facelift by the revised headlamps, tail lamps, wing mirrors, and bumpers.
However all of these things can be retrofitted to an older car easily to make it look younger or if replacing them due to damage. If there’s an indicator in the middle of the front wing then it’s a pre-facelift, if there’s not then it’s probably a facelift.
Reliability still isn’t the greatest but they’re robust cars. Ball joints, suspension, engine mounts and transmission mounts are often neglected. Transmission is generally robust, and personally I would stick to petrol to reduce the potential of repairs.
Replacement suspension springs aren’t available from Mercedes and so a broken spring requires a whole new strut which is expensive. That said, some people have managed to replace the spring on an existing strut, but may not be easy to find and do.
Inside theiy’re generally relatively tough, however the sides of the driver and passenger seats can flatten and wear. Cars with Artico synthetic leather can split in the same place, but can easily be repaired for a reasonable sum.
They use a ladder frame chassis and have low range, so they’re great offroad. However it makes them quite heavy and compromises the ride and handling compared to X5 or Cayenne, but an improvement over Discovery or Shogun.