These beauties were affectionately known as either GM New Look or Fishbowl Buses, owing to the funny looking windshield and backlite. Introduced in 1959, production lasted until 1985 or so, they were the most successful transit bus ever. Powered exclusively by screaming 53 or 71 Series Detroits, the majority of them also had an Allison Automatic Transmission. As a teenager, I rode these daily to Junior High and High School in Tacoma, WA, and I used to always sit in the back right over the motor, so I could hear the 2 stroke powerplant doing battle with the steep hills in Tacoma. The old 2 stroke Detroits were not very efficient or ecology friendly, and when Detroit Diesel had to bite the bullet and build a 4 stroke engine to meet emissions and fuel consumption standards it spelled the end of the line for these buses, because the Series 60 engines would not fit in the engine bay.