1967 Impala

Three days later another car rolled off that same line. No one gave two craps about her, but they should’ve. Because this 1967 Chevrolet Impala would turn out to be the most important car... no, the most important object in pretty much the whole universe.

– Chuck, 5.22 Swan Song

The Impala, of course, has all the things other cars have... and a few things they don't. But none of that stuff's important. This is the stuff that's important: the army man that Sam crammed in the ashtray - it's still stuck there. The Legos that Dean shoved into the vents -to this day, heat comes on and they can hear 'em rattle. These are the things that make the car their's -- really theirs. Even when Dean rebuilt her from the ground up, he made sure all these little things stayed, 'cause it's the blemishes that make her beautiful.

– Chuck, 5.22 Swan Song