Toploader Transmission

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Toploader Transmission

Manufacturer	Ford Motor Company
Also called	Ford Design 4-Speed, 3.03, Top Loader
Production	1964 to 1973
Predecessor	Borg Warner T-10, Dagenham 4 speed
Similar	GM Muncie 4 speed

A Toploader transmission is a manually shifted three and four speed gearbox introduced in 1964 by Ford Motor Company to replace the BorgWarner T-10. It was used in most Fords and Mercurys from 1964 until 1973 as well as some foreign models. Officially designated the 3.03 three speed or Ford design four speed, the Toploader got its name from the fact that the access plate to the inner workings was located on the top of the main case as opposed to the side, a convention used on most gearboxes such as the Ford Dagenham or GMs Saginaw or Muncie. This feature increased the rigidity of the case significantly. Distinguishing the three speed from the four is as simple as counting the fasteners on the top plate. The four speed has ten; the three, nine. By 1967 both the three and four speed gearboxes were designed to function in constant mesh, due to synchronizer sleeves being used instead of sliding gears, and be fully synchronized, with the exception of reverse. Forward gears are helical-type while reverse gear and the exterior of the first and second synchronizers sleeves are spur-type gears.

1 Applications
2 Specifications
3 Gear Ratios
4 See also
5 External links

[edit] Applications

Renowned for high-performance indestructibility, the Toploader, particularly the four speed, was equipped in such sought after "A-list" cars as the Mustang, Talladega, AC Cobra, AC Frua and Sunbeam Tiger as well as the Ford Fairlane, Falcon, Galaxie, Ranchero, Torino and the Mercury Comet, Caliente, Cyclone and Marauder. Overall the Toploader was used in 133 different models and was used extensively in racing as well.

[edit] Specifications

Top and side view, with Hurst shifter.

The Toploader comprises two components: the main case, which encloses the gears, input and counter shaft, and the tailhousing, which encloses the speedometer gear and output shaft. The main case measures 12" in length, while the tailhousing measures 14", 14 1/2" or 17", depending on the application.

Shifter bosses are cast into the tailhousing along various points depending on the location of the shifter, as required for each model. Generally Falcons and Comets have shifters mounted forward along the housing, Mustangs rearward, and Fairlanes and full size Fords somewhere in between. Toploaders were also designed for two specific applications: small blocks like the 289 and 390, and big blocks like the Cobra and Boss. Big blocks required a larger "input shaft" to withstand the torque.

Toploader 4 speed

Application	Engine used (cid)	Toploader Length	Imput shaft OD	Splines, input	Splines, output
Cougar	289, 302, 351	26"	1 1/16"	10	28
Falcon, Comet	170, 200, 260, 289	26"	1 1/16"	10	28
Fairlane 1964-65	170, 200, 260	27 1/2"	1 1/16"	10	28
Fairlane 1967-68	200, 289, 390	26"	1 1/16"	10	28
Maverick	200, 250, 302	26"	1 1/16"	10	28
Mustang 1964-73	200, 289	26"	1 1/16"	10	28
Ranchero 1967-68	200, 289, 390	26"	1 1/16"	10	28
Tiger, TVR	260, 289	27 1/2"	1 1/16"	10	28
Fords, Mercurys	200, 289, 390	29"	1 1/16"	10	28
Ranchero 1969 up	302, 428, 429	29"	1 3/8"	10	31
Fords, Mercurys	428, 429, Boss	29"	1 3/8"	10	31
Mustang 1968 up	427, 428, Boss	26"	1 3/8"	10	31

Note: 1964 and early 1965 Toploaders came with 25 spline output shafts which subsequently proved to be defective and were quickly replaced.

[edit] Gear Ratios

Toploader 4 speed

Close	1st	2nd	3rd	4th
Ratio	2.32	1.69	1.29	1.0
Tooth Count	32	28	25	23
Counter Gear Tooth Count	15	18	21	25
Wide	1st	2nd	3rd	4th
Ratio	2.78	1.93	1.36	1.0
Tooth Count	32	31	25	23
Counter Gear Tooth Count	15	21	24	30