Seattle Transit System #598 is one of a fleet of 100 buses purchased in 1963 through Seattle Transit's Renewal and Betterment Fund, in an effort to modernize, provide transit service to previously unserved areas of the city, and utilize new roadways like the Alaskan Way Viaduct, Fauntleroy Expressway, and completed sections of the Central Seattle Freeway (Interstate 5).

Built by Flxible of Loudonville, Ohio and dubbed "Transi-Cruisers", the arrival of this fleet in the late spring and summer of 1963 enabled Seattle Transit to extend service north of 85th Street to 145th Street, an area annexed by the City of Seattle nearly a decade earlier. This area had been without city transit service due to the system's inability to extend the trolley bus overhead beyond the former city limits at 85th Street. Rush hour express service to and from West Seattle was also now available for the first time. Each neighborhood welcomed the new buses and service with celebrations, complete with district dignitaries and entertainment by such local television celebrities as Stan Boreson and J. P. Patches.

The conversion from trackless trolley to diesel bus marked the end for not only the 100 Renton built Pacific Car and Foundry-Brill trolley buses (one of these, #798 has been preserved by MEHVA in the historic fleet), but the end of trolley bus routes in the northend of the city and West Seattle as well. A citizen's group calling itself COMET - Committee for Modernization of Electric Transit, protested the trolley route abandonments. But the dieselization of these routes to diesel would save the system a half million dollars annually in operating costs alone. So the economics of providing bus service farther out, coupled with the lack of new trolley buses on the market prevailed.

The "500's" (as they were numbered 500-599) were the first "New Look" buses to operate here. The "New Look" was actually a series design standards established by the American Transit Association to make buses more appealing to a dwindling ridership nationwide.

Local newspaper advertisements proclaiming "Seattle Goes High Fashion" touted the new modern buses and their advanced features while promoting the latest in women's fashionable apparel available at Seattle department stores.

Flxible and General Motors each produced their own versions of "New Look" buses. Flxible produced this body style with some variations until 1978 when the model was phased out in favor of their new ADB (Advanced Design Bus) model. Flxible, an American bus builder for over seven decades, went bankrupt and out of business in 1996.

The red and gray color scheme that #598 has been finished in, was designed by Seattle Industrial designer Robert L. Rogers for Seattle Transit in 1968. This scheme, replacing the green and white that had been used on the city's bus fleet since 1955, was an effort to provide a new identity for the transit system and reduced confusion with the similarly painted suburban buses of the Metropolitan Transit Corporation. #598 was the first bus to finish in this bold new livery.

In 1973 Metro Transit was formed, merging the Seattle Transit System and Metropolitan Transit Corporation into a county wide transit agency. By 1975 red and gray began to fade in favor of Metro's new identity, "Sunrise", a combination of brown, ochre and yellow.

After being relegated to rush hour tripper service for many years and then school tripper service, Metro retired the entire "500" series fleet in 1986. Replaced by the boxy looking M.A.N. "Americana" series, fleet #3000-3146, 3150-3159. #598 was picked by MEHVA for preservation and ultimate restoration.

MEHVA volunteers spent hundreds of hours in the painstaking restoration of #598 to it's appearance and operation of the late 1960's and early 1970's. Changes to this fleet over the years presented many challenges to the restoration process. Original hand crank sign components had to be located and some fabricated from scratch. The Jacob's Engine "Jake" Brake was made operational again. Seattle Transit graphics were recreated both inside and out. Special paint was used to simulate the anodized aluminum on the fluted body panels. Even the original 1963 license plates have been restored.

The restoration of Seattle Transit System #598 was funded by the Metro Employees Historic Vehicle Association (MEHVA) in cooperation with King County Metro Transit and through a grant SUPPORTED BY THE KING COUNTY LANDMARKS AND HERITAGE COMMISSION HOTEL MOTEL TAX REVENUES.