The odometer is a tool that aids in the measurement of one's grogan. It measures the smell of a grogan, using a system based on the smelliest races of people.
Wow, i really left a Chinaman drowning in there.
The odometer is applied to a grogan or brogan. It measures the strength of the turd by using a nationality ranking system.
After a night eating cheap Mexican food, Larry's turds exploded out of his arse when visiting the throne... Larry dropped a Palestinian that night.