Dog-leg gearbox

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A Dog-Leg Gearbox is a manual transmission shift pattern distinguished by an up-over-up shift between first and second gear.[1] The layout derives its name from a dog's hind leg, with its sharp angles.

Dog leg five-speed layout Typical five-speed layout
Manual Dogleg.svg Manual Layout.svg

Automobiles[edit]

Dog leg layout gearboxes are desirable on performance cars because in road racing more frequent shifting occurs from second to third than from first to second gear.

Examples of cars that have used this pattern for performance reasons include the BMW M535, Early 635CSi (non-US) and (non-US) M3 E30, BMW 2002 Tii and Turbo, Fiat Dino 2.4 (ZF Box), Mercedes-Benz 190E 2.3-16 and 2.5-16, Mercedes-Benz 300 CE-24, Ferrari 308 GTB/GTS, Ferrari Testarossa, Porsche 914, early 911, 924 Turbo (all featuring Getrag gearboxes), Cosworth Vega, Porsche 928, Talbot Sunbeam Lotus, Vauxhall Firenza HPF, Lancia Fulvia, Lancia Stratos, Lamborghini Countach, Maserati Biturbo, and De Tomaso Pantera.

Despite the performance benefits, non-performance-oriented cars available with the dog-leg shift pattern were produced. Examples include the Ford Model A, Subaru 360, Datsun 160J Hardtop SSS, 74–77 Datsun 610 SSS, 78–80 Datsun 200sx, 1980 Datsun 210 Wagon (built during the 210/310 crossover), 78–80 Datsun 510, Citroën 2CV, Mercedes 190, Mercedes-Benz 200D, Mercedes-Benz 300CE, Mercedes-Benz 320CE, Mercedes-Benz E320 sedan -94 and the 1976–77 Oldsmobile Cutlass or Pontiac LeMans with the 260 V8, the 76–77 Chevrolet Vega or Pontiac Astre, 76–79 Chevrolet Monza or Buick Skyhawk or Oldsmobile Starfire, BMW E21 and the 77–79 Pontiac Sunbird. The early model Renault 4 had a distinctive 'umbrella handle' dog-leg shift, which proved ideal for urban driving, though the shift was later changed to the 'conventional' pattern.

Trucks[edit]

Many light trucks have dog-leg five- or six-speed transmissions, due to the fact that second gear is fine for taking off normally, first is considered a crawler gear in these trucks and is only ever used for taking off with heavy loads and/or a trailer, or going down very steep grades.

The dog leg gearbox is also typical of nine- and ten-speed heavy-truck transmissions. In the case of a ten-speed transmission, the gears are 1–5 in the low range and 6–10 in the high range (the 1 position is not used in the high range of a nine-speed transmission).

References[edit]

  1. ^ Paternie, Patrick (December 31, 1999). How to Restore and Modify Your Porsche 914 and 914/6. Motorbooks. p. 107. ISBN 9780760305843.