Greasy's Diner is a local diner in Gravity Falls, Oregon. It is a typical restaurant that serves breakfast pancakes and other traditional American food. Mabel, Dipper, Wendy, and Grunkle Stan all go to eat regularly at Greasy's Diner.
In "Dipper vs. Manliness", the Pines family go there for breakfast, and Dipper ends up humiliating himself on the Manliness Tester. Grunkle Stan crushes on Lazy Susan, one of the diner's waitresses, but is too afraid to ask her out, so Mabel, Wendy, and Soos all help him get out of his lazy stage and help him be more appealing. At the end of the episode, Lazy Susan slips her phone number to Grunkle Stan, and in the ending credits, he receives several voicemails from her.
The outside of Greasy's Diner is in the shape of a fallen redwood log. There is even the stump of a redwood located on its right, as though the tree was chopped down right there and made into the restaurant. Underneath the main sign bearing the diner's name is a smaller sign with the slogan "We have food". The diner is on a train car that is labeled "Gravity Falls 1883", with steps leading to the entrance and back door. Somewhere close (short walking distance) there is a pay phone (as seen in Society of the Blind Eye).
Greasy's Diner is also home to the "Test Your Manliness" machine. This machine becomes central to the plot of "Dipper vs. Manliness." The harder you squeeze the handle, the more bulbs will light up. If one reaches "Manly Man," the prize is free pancakes. Dipper fails the test, so he goes into the woods to become more manly. Manly Dan achieved "Manly Man" with only his pinkie finger, causing the machine to explode and shower everyone with free pancakes.