Brian:
Is the Federal standard for bumbers 2.5 or 5 mph, anyone know? I am as amazed as you are about the poor bumper performance, but the bumper has relatively little to do with occupant safety after about 20mph - I understand that it is there mostly to preserve the body work at lower speeds. I believe that the body engineering (crumple zones, spare storage, gas tank location, structural rigidity of the passenger safety cage, etc.) have more to do with occupant safety.
An example would be the egg drop contest that many junior high students perform in their science classes. Some students construct containers that survive a drop from a 6 story building unscathed, but the contents are raw omlette. Other containers are completely totalled, but the egg is unscathed.
For MB to put a rear bumper on a car that sustains $1100 damage after a 5mph collision is unconscionable (unless it is part of an engineered crumple system, in which case they should be a little upfront about it). However, I would like to see the comparison of crash dummy test results for a 40 mph rear end collision on the 2 cars before I made a safety choice. Sorry I missed the show.

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

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