Motor Coach Industries D-Series

The Motor Coach Industries D-Series is a line of intercity motorcoaches. It has become a workhorse of the motorcoach industry and is one of North America's best-selling coaches.

History

In 1988, MCI began development of a wheelchair accessible intercity coach with a grant from the Government of Canada. The 45-foot coach was first displayed in May of 1990. It had a wheelchair lift at the rear and an accessible lavatory.

Launched in 1992, the new 45-foot coach was named the 102-DL3. It featured a larger engine compartment than previous coaches, which could accommodate the new Series 60 engine from Detroit Diesel. Components such as HVAC and fuel tank were moved further back to improve weight distribution. A 40-foot version, named the 102-D3, was introduced in 1994.

In August 2000, MCI announced a new model name convention. The 102-D3 became the D4000 and the 102-DL3 became the D4500. A multiplex electrical system and new sliding wheelchair door were launched in 2001. The automated manual ZF AS Tronic transmission also became an option.

The D-Series was redesigned in 2005. The Phase I design, later designated Contemporary or "CT", features new headlights like those on the G-Series and flush-mounted passenger windows. The Phase II design is geared toward charter and tour operators. It features a curved front end, rounded off bumpers and fenders, flush-mounted passenger windows, and more interior amenities. The legacy design was designated Classic or "CL".

In order to accommodate EPA 2007 engines MCI had to modify the rear of the D-Series. The opportunity was also taken to refine the styling of the coach as well as revise the side-by-side radiator and charge air cooler. The revised radiator and charge-air-cooler boast quieter operation and greater cooling capacity.

For coaches meeting the EPA 2010 standards, MCI re-engineered their cooling package again. The new system comprises of a single fan with a three speed clutch and shorter belt. Coaches equipped with this new package are identifiable by the two small vents added on the upper corners of the rear. Some EPA 2007 coaches were also built with the new cooling package.

The two EPA 2010-compliant engines available for the D-Series are the Cummins ISL9 and ISX12. MCI considered the Detroit Diesel DD13 as an option, but this has not developed further than the evaluation stage. All engines were initially only available with the Allison transmission, with the ZF transmission not available until later in 2011.

At the end of the 2014 model-year, the D-Series adopted the ceiling and new parcel rack design from the J4500. The new parcel racks afford passengers more head room and feature new multisets with improved layout and illuminated "fasten seatbelt" sign. The way the racks are mounted also eliminates the space between them and the wall above the windows.

Likely as a request from New Jersey Transit, their 2014 batch of D4500CT coaches were delivered with redesigned headlights. This simplified design has three round LED clusters arranged in a gently curving row. Other operators, such as Broward County Transit and GO Transit have adopted the same headlights.

At the 2017 American Public Transportation Expo in Atlanta, Georgia, MCI introduced the first of their next-generation D-Series coaches geared to Commuter Rapid Transit (CRT). These coaches are directly based on the J4500 but marketed under the D-Series name, and have little relation to previous D-Series coaches. The D45 CRT LE features a patent pending low entry vestibule near the middle of the coach. This low floor section allows for those using mobility aids easier access to the interior of the coach. Between 2018 and 2022, more models were introduced including a battery-electic model. This line of coaches has new features and a new striking appearance.

Model number breakdown

Model Number	Years of manufacture	Image	Length (feet)	Width (inches)	Notes
102-D3	1994-2000		40'	102"
102-DL3	1992-2000		45'	102"
D4000	2001-2005		40'	102"
D4000H			40'	102"	Diesel electric hybrid prototype buses. 4 units produced, all for NJ Transit.
D4000N			40'	96"	12 units produced, 8 for Pace and 4 for NJ Transit.
D4500	2001-2005		45'	102"
D4000CL	2005-2013		40'	102"	"Classic" design
D4500CL	2005-2013		45'	102"	"Classic" design
D4000CT	2005-present		40'	102"	Frameless windows, G-Series headlights, "Contemporary" design
D4500CT	2005-present		45'	102"	Frameless windows, G-Series headlights, "Contemporary" design
D4500CTH	2008-2016		45'	102"	Frameless windows, G-Series headlights, "Contemporary" design, diesel electric hybrid
D4005	2005-2021		40'	102"	Frameless windows, G-Series headlights, sleeker design
D4505	2005-2021		45'	102"	Frameless windows, G-Series headlights, sleeker design
D45 CRT LE	2017-present		45'	102"	Next generation D-Series based on J4500. New styling and low entry vestibule.
D45 CRT LE CHARGE	2020-present		45'	102"	Next generation D-Series based on J4500. New styling and low entry vestibule. Battery-electric powered.
D4020	2020-present		40'	102"	Next generation D-Series based on J4500. New styling.
D4520	2020-present		45'	102"	Next generation D-Series based on J4500. New styling.
D45 CRT	2021-present		45'	102"	Next generation D-Series based on J4500. New styling.
D45 CRT LR	2021-present		45'	102"	Next generation D-Series based on J4500. New styling. Low roof.
D45 CRT CHARGE	2022-present		45'	102"	Next generation D-Series based on J4500. New styling. Battery-electric powered.
D40 CRT	Launching in 2022		40'	102"	Next generation D-Series based on J4500. New styling.

Inmate Security Transportation Vehicle (ISTV) models

The 102D3 (and later D4000) ISTV coaches are used mostly as prison inmate transport vehicles and can be customized with exterior window bars and small 5" windows. They are only available in the 40-foot length option.