Editing Ford Model T (section)

====Aftermarket transmissions and drives====

During the Model T's production run, particularly after 1916, more than 30 manufacturers offered auxiliary transmissions or drives to substitute for, or enhance, the Model T's drivetrain gears. Some offered overdrive for greater speed and efficiency, while others offered underdrives for more [[torque]] (often incorrectly described as "power") to enable hauling or pulling greater loads. Among the most noted were the Ruckstell two-speed rear axle, and transmissions by Muncie, Warford, and Jumbo.<ref name="auxiliary_transmissions_1921_fahnestock">{{citation |last=Fahnestock |first=Murray |url=https://www.nwvs.org/Technical/MTFCA/Articles/1803ExtraTransmissions.pdf |title=Multi-Speed Transmissions: Utility and Pleasure of Auxiliary Transmissions |year=1921 |magazine=Ford Owner and Dealer |via=Vintage Ford (Model T Ford Club of America) |access-date=November 30, 2022}}</ref><ref name="auxiliary_transmissions_ted_aschman">{{citation |last1=Aschman |first1=Ted |last2=Houston |first2=Fred |last3=Klehfoth |first3=Jay |url=https://www.nwvs.org/Technical/MTFCA/Articles/2602AuxilaryTransmissions2.pdf |title=I Didn't Know That!: Auxiliary Model T Transmissions |date=March 1991 |magazine=Vintage Ford |publisher=Model T Ford Club of America |access-date=November 30, 2022}}</ref>

Aftermarket transmissions generally fit one of four categories:
* ''Replacement transmission'' – usually a sliding gear/selective transmission, intended as a direct replacement for Ford's planetary-gear transmission.<ref name="auxiliary_transmissions_ted_aschman" />
* ''Front-mounted auxiliary transmission'' – designed to fit between the engine and Ford's transmission, to add additional gear ratios.<ref name="auxiliary_transmissions_ted_aschman" />
* ''Rear-mounted auxiliary transmission'' – mounted at the rear axle housing, and attached between it and the driveshaft, to add additional gear ratios.<ref name="auxiliary_transmissions_ted_aschman" />
* ''Multi-speed axle'' – designed to fit ''inside'' the differential's housing, to add additional gear ratios.<ref name="auxiliary_transmissions_ted_aschman" />

Murray Fahnestock, a Ford expert in the era of the Model T, particularly advised the use of auxiliary transmissions for the enclosed Model T's, such as the Ford Sedan and Coupelet, for three reasons: their greater weight put more strain on the drivetrain and engine, which auxiliary transmissions could smooth out; their bodies acted as sounding boards, echoing engine noise and vibration at higher engine speeds, which could be lessened with intermediate gears; and owners of the enclosed cars spent more to buy them, and thus likely had more money to enhance them.<ref name="auxiliary_transmissions_1921_fahnestock" />

He also noted that auxiliary transmissions were valuable for Ford Ton-Trucks in commercial use, allowing for driving speeds to vary with their widely variable loads – particularly when returning empty – possibly saving as much as 50% of returning drive time.<ref name="auxiliary_transmissions_1921_fahnestock" />