I hope you guys remember this bus a while ago before conversion. It's the TTC 1996 Orion V CNG!
These buses were supposed to be part of an order for 100 CNG-powered Orion VI low floor accessible buses. However in an attempt to expedite delivery after production delays, half of the order was built as lift-equipped high floor buses.
The buses were still powered by CNG and used a Cummins L10G engine. The TTC's experiment with CNG fuel was not successful (especially after tank design issues forced this series off the road temporarily in 1997). Unlike the 9200 series Orion VI CNG buses that were retired, the entire 9400 series was converted from CNG to diesel power (Cummins M11 Engine with Allison World B400R Transmission).
These buses retired in 2015, may them R.I.P :'(
Engine:
Cummins L10G engine
Transmission:
Allison World B400R (5 speed)
(Note: Audio not mine, is from this link here: www.transithub.net/sounds.htm and it's recorded by Allen Dicion (I think)