Bus Stop Classics:  Marmon-Herrington (M-H) TC 44/48 – Post-War America’s Favorite Trolleybus

Dayton TC48.  Photo by Steve Morgan.


Trolleybuses (initially called trackless trolleys) were once a fixture on American streets, either replacing or supplementing iron-rail trolleys.  Prior to WW II, the three primary US trolleybus manufacturers were ACF-Brill, Pullman, and the St Louis Car Company – all three of which began as producers of locomotives, trolley-cars, and/or rolling stock.  But a newcomer was introduced in the immediate post-war period whose expertise was more in 4WD rubber-tired vehicles, and who would quickly rise to the top of the trolleybus sales charts.

1940 Ford M-H 4WD Conversion


M-H Indianapolis Factory


Like their gas and diesel equivalents, trolleybuses made in the 1920’s and ‘30’s were tired from constant, hard wartime use and ready for replacement when the war ended.  M-H produced off-road trucks and was a successful aftermarket supplier and partner to the major manufacturers in 4WD conversions of their trucks and station wagons.  It was looking for a market segment to enter to replace its extensive wartime contracts, and saw an opportunity in the trolleybus market.  In turn, in 1945 it constructed a new factory in its hometown of Indianapolis. 

TC48 – Philadelphia


The first buses emerged in 1946; the principal models were the TC44/46 and TC48/49, with the numerals denoting the number of seats.  A single order for a 40-seat TC40 model was produced for San Francisco.  The TC44/46 was thirty-six feet in length, the TC48/49 thirty-nine feet, and the TC40 thirty-three feet.  General Electric motors and controllers were used, and they operated on 600/800 volts DC.

The buses were immediately successful, for several reasons.

Cost.  M-H’s new factory in Indianapolis was for its time state-of-the-art, significantly streamlining the manufacturing process and allowing the company to lower per unit price.  This at a time before government grants and subsidies when transit authorities had to fund the entire capital cost of their fleets.

Low Weight.  Like the GM Old Look, M-H used stressed-skin monocoque construction resulting in a much lighter bus, allowing for faster speeds, less damage to roads, and smaller electric motors/components, increasing interior space.  Total weight for an unloaded TC49 was roughly 20,000 lbs which was about 4.000 lbs lighter than its competitors.  

Durability.  Besides the monocoque body, the coach also utilized high-strength double-girder steel side-rails, along with multiple steel alloy crossmembers, which made for an extremely rigid design.   

TC48 – San Francisco Bicentennial


A total of 1,624 trolleybuses were produced from 1946 to 1959. 

It maintained its original styling during the production run, though some operators did their own modifications – SEPTA (Philadelphia) updated the electrical components and added a new front with dual-headlights from a GM New Look.    

Ex-Chicago Mexico City


Testament to their durability, in my hometown of Columbus Ohio, thirty-two 1948 models were sold to Dayton in 1967.  Twenty of these were refurbished (twelve used for parts) and continued to provide excellent service for another 15 years.  In addition, the last of Chicago’s were retired in 1973 and Philadelphia’s in 1981.  Some of these were then sold to Mexico City and continued in service until 1988.  A portion were re-built with updated coachwork and remained on the road until 2002.

I had the opportunity to ride these M-H’s in my younger days — they were mostly silent except for the “”whrrrr” of the electric motor.  The downside was they lacked an airbag suspension — it was all steel springs which meant a lightly loaded bus rode extremely hard and the silent motor was offset with a cacophony of bumps, bangs, and rattles.  Pity the driver and passengers in a lightly loaded bus on a potholed road.  The other thing I remember clearly were the large, dual-folding front doors, which allowed for entering on one side and exiting on the other.

Fun Fact:  Is it “trolleybus” or “trolley bus?”   The internet states either is acceptable – Merriam-Webster and the Cambridge dictionary say “trolleybus”, which I’ve used.