Interestingly enough, there is a reference to be googled for metridge:

"Dear Digest,

You are an innocent traveler in time and space, navigating a strange unexplored frontier called... the information superhighway, when you stumble upon a conundrum upon your favorite digest...

..."The Twilight Zone Brake Malady Riddle"...

THE CAR-

... an '88 4AGZE, clean, 73,6XX.X miles (multiply by 1.609 for "metridge").

http://www.mr2.com/DIGEST/VOLUME1/1494.txt
It's nearly at the bottom of the page.