While on that topic, isn't it interesting that although the same info (mechanical or electrical) is fed to the speedo and odo, that the odo on earlier cars sometimes fail, while the speedo keeps on chugging?
2009 ML350 (84K) - Family vehicle
2001 CLK430 Cabriolet (71K) - Wife's car
2005 BMW 645CI (124K) - My daily driver
2012 Mustang V6 (60K) - Daughter's car