King County Metro fleet
As of 2017, King County Metro operates the 10th largest fleet of buses in the United States, with a total of 1,540 buses.
Upon taking over transit operations on January 1, 1973, Metro used buses acquired from predecessor agencies Seattle Transit System and the Metropolitan Transit Company, still painted in their original colors. Metro acquired the 91-bus fleet of the Metropolitan Transit Company in December 1972 at a cost of $2.75 million. The first fleet of new buses ordered by Metro arrived in June 1976, consisting of 145 diesel coaches manufactured by AM General. In 1978, Metro became the first large transit agency in North America to introduce articulated buses to its fleet, which required some bus stops to be rebuilt to accommodate coaches. The fleet of 151 buses were manufactured by German maker MAN as part of a bulk order with other large U.S. transit agencies.
Vehicle types
In 1978, Metro was the first large transit agency to order high-capacity articulated buses. Today, King County Metro has one of the largest articulated fleets in North America and articulated buses account for about 42% of the agency's fleet.In 1979, the agency ordered some of the first wheelchair lift equipped coaches in the nation, promising a completely new level of independence for disabled residents. Early lifts were severely flawed, but by the mid-1980s the lifts were generally reliable and were ordered on all new buses. Metro's entire fleet has been wheelchair-accessible since 1999.
Metro was reluctant to adopt low-floor buses, not buying any until 2003. Low-floor coaches have slightly reduced seating capacity which may have been a concern. Whatever the reason for the delay, Metro has now embraced low-floor buses and all new fleet additions since 2003 have been low-floor and the last high-floor buses are scheduled to be retired in 2018.
Trolleys
Metro maintains a fleet of electric trolleybuses that serve 15 routes along almost 70 miles of two-direction overhead wire. This is the second largest trolleybus system in the United States by ridership and fleet size. The trolleybuses are valued by Metro both as zero-emission vehicles, and as vehicles well adapted to Seattle's hilly terrain.Metro's trolleybus fleet consists of 174 entirely low-floor New Flyer Xcelsior coaches. Of the total, 110 are vehicles and 64 are, articulated buses. The buses include an auxiliary power unit, to allow them to operate off-wire for up to.
Occasionally Metro will use diesel or diesel-electric hybrid coaches on trolley routes. Reasons for doing this include construction, overhead wire maintenance or events that require coaches to go long distances off-route, "coach changes" or to add temporary additional capacity. The latter two cases sometimes lead to diesel buses being used, in order to get the replacement or supplementary vehicle into service as quickly as possible; diesel buses can reach the point of entry into service faster, as they do not need to follow the overhead wires when deadheading.
Diesel-electric hybrids
Metro operates the largest fleet of hybrid buses in the country. The first hybrid buses were purchased in 2004 for use with routes that operated in the Downtown Seattle Transit Tunnel. The National Renewable Energy Laboratory conducted a one-year comparative study between conventional diesel and hybrid-powered buses operating on a typical King County drive cycle. Results showed that the hybrid powered buses lowered fuel consumption by 23%; NOx by 18%; carbon monoxide by 60%; and total hydrocarbon by 56% when compared to conventional diesel buses. Those results have led Metro to purchase hybrid buses exclusively since 2005. Metro now has over 700 hybrid buses in the fleet, with more on order.Hush mode
Buses equipped with the GM-Allison EP50 and the Allison H 50 EP parallel hybrid systems have a special "hush mode" that allows the buses to operate solely on electric power, reducing tailpipe emissions and noise while operating in the Downtown Seattle Transit Tunnel. Before entering the tunnel, the operator pushes a button that puts the coach into hush mode. While buses are inside stations, the coaches operate solely on electric propulsion. In between the tunnel's stations, the bus uses electric traction to get to, after which a combination of the electric and diesel motors are used. The operation of the diesel engine allows the batteries to recharge. Hush mode is normally deactivated by the operator as they exit the tunnel, but the mode will be automatically deactivated after the coach has traveled a certain distance.Series hybrids
Metro's newest buses are equipped with the BAE Systems HybriDrive, a series hybrid system.Flyer Transfer"> In these buses an electric motor turns the wheels, with power provided by a generator attached to a diesel engine and regenerative breaking. Any excess power is stored in batteries on the roof of the bus. Because the diesel engine is not directly propelling the bus, it can operate at a more steady, fuel-efficient speed.Buses delivered after 2014 are equipped with the upgraded HybriDrive Series-E which uses electrically powered accessory systems to increase fuel efficiency and allow the diesel engine to stop when the bus is stopped and the batteries are sufficiently charged.
Battery electric buses
Metro began testing three new Proterra Catalyst battery electric buses in 2015. The coaches are capable of traveling over 26 miles before the battery needs to be recharged. A special fast charge station located at the Eastgate Park and Ride allow the bus to be fully recharged in under 10 minutes, during the driver's normally scheduled layover. These new vehicles get the equivalent of 20.8 MPG, which is over 6 times better than the 3.18 MPG seen on Metro's series hybrid electric coaches. The coaches were purchased with support from a $4.7 million Federal Transit Administration grant and entered revenue service on February 17, 2016. They operate on shorter routes on the eastside, specifically Routes 226 and 241.. Metro has committed to purchasing 120 electric buses with the option to purchase up to 80 additional vehicles by 2020. In 2017 and 2018, Metro tested electric buses with ranges of 140 miles from several manufacturers, and plans to have a zero-emissions bus fleet by 2040.Historic preservation
Metro has a special fleet of more than a dozen historic motor buses and trolleybuses ranging from ones built in the late 1930s and early 1940s through to ones only recently retired. The coaches are restored, maintained and operated under an agreement with the Metro Employees Historic Vehicle Association, a non-profit organization formed in 1981. Metro maintains ownership of the historic fleet, providing coverage under its fleet self-insurance along with storage, work space and parts on an as available basis.Money to operate the coaches and purchase parts not in Metro stock is generated by selling tickets to public excursions. The first trips took place in 1984, and nowadays MEHVA typically operates six to eight per year. Each excursion has a different route and a different emphasis.
MEHVA was established in 1981, as Metro prepared to retire trolleybuses that had been operating in Seattle since the 1940s. Since that time, MEHVA acquired other retired transit vehicles which were formerly operated in King County. Often these retired coaches were purchased by private citizens and left on the owner's property for many decades, leaving them in need of restoration. The collection of vehicles has gradually expanded over time, with the addition of newly retired buses when deemed historically notable and not yet represented in the collection.
Current fleet roster
Future fleet
Historic fleet
These historic buses are owned by King County Metro, but are restored, maintained and operated by unpaid volunteers who are in the Metro Employee Historic Vehicle Association.| Make/Model | Length | Thumbnail | Propulsion | Year | Purchasing Agency | Fleet Number |
| Kenworth H-30 | Diesel | 1938 | Seattle Municipal Street Railway | 1705 | ||
| Twin Coach 30-G | Diesel | 1939 | Seattle Transit System | 231 | ||
| Twin Coach GWFT | 40 feet | Electric trolleybus | 1940 | Seattle Transit System | 905 | |
| PCF-Brill 40 SMT | 40 feet | Electric trolleybus | 1940 | Seattle Transit System | 798 | |
| Twin Coach 44 GTT | 40 feet | Electric trolleybus | 1943 | Seattle Transit System | 636 | |
| Pullman-Standard 41CA-100-44CX | 40 feet | Electric trolleybus | 1944 | Seattle Transit System | 1005 | |
| Kenworth K-10 | Diesel | 1947 | Suburban Transit System | 86 | ||
| Twin Coach 41-S | Diesel | 1948 | Seattle Transit System | 1705 | ||
| General Motors TDH-5105 | 40 feet | Diesel | 1955 | Seattle Transit System | 263 | |
| General Motors TDH-4512 | 40 feet | Diesel | 1959 | Metropolitan Transit Corporation | 2962 | |
| Flxible New Look F2D6V-401-1 | 40 feet | Diesel | 1963 | Seattle Transit System | 598 | |
| General Motors New Look T8H-5305 | 40 feet | Diesel | 1968 | Seattle Transit System | 724 | |
| AM General 10240B | 40 feet | Diesel | 1976 | Municipality of Metropolitan Seattle | 1122 | |
| AM General 10240T | 40 feet | Electric trolleybus | 1979 | Municipality of Metropolitan Seattle | 1008 | |
| MAN/AM General SG 220-18-2 | 60 feet | Diesel | 1979 | Municipality of Metropolitan Seattle | 1455 | |
| Flyer D10240C | 40 feet | Diesel | 1979 | Municipality of Metropolitan Seattle | 1657 | |
| MAN Americana SL40102L | 40 feet | Diesel | 1987 | Municipality of Metropolitan Seattle | 3152 | |
| Breda DuoBus 350 | 60 feet | Dual-mode | 1990 | Municipality of Metropolitan Seattle | 5034 | |
| Gillig Phantom 40102TBM11 | 40 feet | Diesel | 1997 | King County Metro | 3374 | |
| Gillig Phantom C28D102N4 | 40 feet | Electric trolleybus | 2002 | King County Metro | 4195 |
Retired fleet
| Thumbnail | Make/Model | Propulsion | Motor/Powertrain | Seated Capacity | Length | Purchased | Retired | Qty. | Fleet Numbers |
| Brill trolley | Electric trolleybus | GE | 40 | 40' | 1940 | 1963 | 100 | 700–799 | |
| Twin Coach trolley | Electric trolleybus | Westinghouse | 41 | 40' | 1940 | 1978 | 177 | 800–976 originally ; remaining coaches in 1974 renumbered into series 600–659. No. 905 preserved by Metro. | |
| Pullman-Standard trolley | Electric trolleybus | GE | 44 | 40' | 1944 | 1978 | 30 | 977–1006 originally; 642–655 from 1974 until end of service. No. 1005 preserved by Metro. | |
| GMC TDH-5105 | Diesel | 51 | 40' | 1955 | 1982 | 105 | 200–304. No. 263 has been preserved by Metro. | ||
| Flxible "New Look" | Diesel | Detroit Diesel 6V71 | 51 | 40' | 1963 | 1986 | 100 | 500-599 | |
| GMC "New Look" T8H-5305 | Diesel | Detroit Diesel 8V71N/ Allison VS2-8 | 48 | 40' | 1968 | 1987 | 70 | 700-769 | |
| AMG 10240B8 | Diesel | Detroit Diesel 8V71N Detroit Diesel 8V71T Allison V730 | 45 | 40' | 1976 | 1996 | 323 | 1100–1313; 1340-1349 | |
| MAN SG-220 | Diesel | MAN D2566 MLUM/ Renk-Doromat 874B | 72 | 60' | 1978–1979 | 1999 | 151 | 1400-1550 | |
| Flyer D900 | Diesel | Cummins VTB903/ Allison V730 | 47 | 40' | 1979 | 1997 | 224 | 1600-1823 | |
| AMG 10240T | Electric trolleybus | GE | 45 | 40' | 1979 | 2003 | 109 | 900-1009 | |
| Flyer D900 | Diesel | Cummins VTB903/ Allison V730 | 39 | 35' | 1980 | 1997 | 35 | 1850-1884 | |
| MAN SG-310 | Diesel | MAN D2566 MLUM/ Renk-Doromat 874B | 70 | 60' | 1982–1983 | 2001 | 202 | 2000-2201 | |
| MAN Americana | Diesel | MAN D2566 MLUH/ Renk-Doromat 874B | 44 | 40' | 1986–1987 | 2004 | 157 | 3000-3146; 3150-3159 | |
| MAN ETB | Electric trolleybus | Siemens | 64 | 60' | 1987 | 2007 | 46 | 4000-4045 | |
| Breda DuoBus 350 | Dual-mode | Diesel: Detroit Diesel 6V92TA/ ZF 4HP600 Electric Trolley: AEG/Westinghouse | 56 | 60' | 1988–1991 | 2005 | 236 | 5000–5235 | |
| Breda DuoBus 350 | Electric trolleybus conversion | AEG/Westinghouse | 56 | 60' | 1988–1991 | 2016 | 59 | 4200–4258
| |
| Gillig Phantom | Diesel | Cummins M11/ Allison B400R Gen III | 34 | 35' | 1997 | 2015 | 13 | ||
| New Flyer D60HF | Diesel | Cummins M11/ Allison B500R Gen III | 64 | 60' | 2018 | 274 | |||
| Gillig Phantom | Electric trolleybus | GE | 42 | 40' | 2002 | 2016 | 100 | ||
| New Flyer D60LF | Diesel | Caterpillar C9/ Allison B500R Gen IV | 56 | 60' | 2004 | 2018 | 30 | ||
| StarTrans President LF | Diesel | GMC/Duramax Allison 1000 series | 19 | 28' | 2009 | 2013 | 35 | 1900-1934
| |
| Gillig Phantom | Diesel | Cummins M11/Allison WB-400R | 42 | 40' | 1996–1999 | 2019 | 395 | 3200-3594 | |
| Gillig Phantom | Diesel | Cummins ISC/Allison WB-400R | 30 | 30' | 1999-2000 | 2020 | 95 | 1100-1194
| |
| New Flyer D40LF | Diesel | Cummins ISL/Voith 864.3 | 35 | 40' | 2003 | 2020 | 100 | 3600-3699
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