Quote:

EPDM rubber (ethylene propylene diene monomer rubber) is an elastomer which is characterized by wide range of applications. EPDM rubber is used in vibrators and seals; glass-run channel; radiator, garden and appliance hose; tubing; washers; belts; and electrical insulation. It is also used as a medium for water resistance in high-voltage polymeric cable jointing installations, roofing membrane, geomembranes, rubber mechanical goods, plastic impact modification, thermoplastic, vulcanizates, as a motor oil additive, pond liner, electrical cable-jointing and chainmail applications.

EPDM exhibits satisfactory compatibility with fireproof hydraulic fluids, ketones, hot and cold water, and alkalis, and unsatisfactory compatibility with most oils, gasoline, kerosene, aromatic and aliphatic hydrocarbons, halogenated solvents, and concentrated acids.

Apart from being used in female entertainment devices its not compatible with most oils, gasoline, etc. So I reckon it must be a drain tube from somewhere.

The only other clue's are, I had just removed the remains of the rear mudflaps, and there was a lot of crap stuck behind them, it could have fallen out with the crap. The other thing is that it possibly came from somewhere else and got blown there by the jet washer.