Is it this one: Laughing as a Young Man Laughs (http://natt.livejournal.com/180817.html) by natt
Summary: Usually, when Death is involved, the earth shatters and apocalypses threaten mankind. Only worse things happen, bigger catastrophes — like when Death finds out that his beloved Cadillac's carburetor is ruined and his trusted mechanic has perished. A story about two lonely men, about classic cars and the hunt for the perfect 1959 62 Series spare part, involving Ebay, fast food and, as strange as it might sound, love and little brothers.