I worked with a guy that religiously sent oil from ALL his equipment for analysis.
He had a...
wait for it...
a Toyota Cellica.
For fun we'd get him started about what oil he used and what we should use.
He was so convinced that certain brands/types were bad, that he spent an entire weekend running around to all the auto parts stores buying up the Castrol in the red cap because it was the German Catrol that didn't have some particular additive.
He stored all these cases (like over a hundred) in his basement so that he'd never run out.
He gave me all his Amsoil 2 stroke oil (about 6 quarts) because he was convinced it ruined his weed eater...
Used to use oil analysis on large industrial diesels quite a bit. A one time test isn't worth the postage but done on a regular basis it will show trends that may become costly if ignored.
