Like I have indicated before, many vehicles are designed for ease of assembly, not repair. Yes, you can keep them going but at what cost/mile?

I will give you another example of basic maintenance that is not economical. The spark plugs in an Lexus RX300 are designed for 100,000 mile replacement intervals, but if you keep the vehicle this long and need to replace the plugs, the ones up against the firewall are inaccessible unless you loosen the engine mounts and tilt the V-6 engine forward!

Someone mentioned planned obsolescence of an MB. Look around you and see how many 10+ year old Toyota's, Nissan's, Lexus's, Infiniti's and other Asian products you even see on the road out there. Probably the main reason you see this is the cost of repairs on these vehicles exceeds the value of the vehicle after the 10 year/100,000 mile point.