take a look at the inside and outside of his bus and hear a little bit of the engine as it dries past this old restored bus from the early 70s was on display so I decided to take a video of it.
This here is a Motor Coach Industries MCI mc6. This bus has a Detroit Diesel turbocharged 8 V 71 with a 4 speed Allison automatic transmission. This is bus is 4169, as numbered by the owner, Frank Gonzalez of Stardust Tours. This bus originally had when it was manufactured a Detroit Diesel 12v 71 with a 4-speed mechanical transmission. There were only 100 of these buses ever made all of them were for Greyhound originally. In this video you can take a look at the inside of the bus and the outside of the bus and you can hear the engine a little bit as the unit drives past me. I saw this bus at the Museum of bus transportation Spring Fling in Hershey Pennsylvania.
The Motor Coach Industries MC-6 was a motor coach produced from 1968-1969. Greyhound had helped design it and intended it as a replacement for the Scenicruiser. Unlike the MC-7 it was an entirely different ultra-modern design and MCI's first 102 inch wide bus. The prototypes had the third axle covered by a body panel.
102 were built in total.
Engine
Detroit Diesel 12V71 (original engine)
Detroit Diesel 8V71T (revised powertrain for US units only, 1977) [1]
Transmission
Manual transmission (original transmission)
Allison HT-740 (revised powertrain for US units only, 1977)
Operators
Canada 
Greyhound Canada
United States 
Greyhound USA
