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How Many Gears Do Nascar Cars Have?

I was wondering how many gears nascar cars, or race cars in general have. also, how many gears do trucks have? ive heard that its like 15 sometimes, but how does the shifting work with that many gears?

Asked by:goldglove93


  1. glen t says:

    Nascar 4&reverse I drove one with 18 forward and 3 reverse most common now is a super 9 or 10 speed It shifts just like a car only you will have one or two splitters (a valve that moves the trans into higher gears) then you use the same pattern to shift from say 1-5 split then6-11 split then12-18

  2. The Intimidator! says:

    Nascar uses a four speed manuel transmission in all makes of cars

    . Because of the wide variety of loads the “semi” may carry, they usually have a manual transmission to allow the driver to have as much control as possible. However, all truck manufacturers now offer semi-automatic transmissions (manual gearboxes with automated gear change), as well as automatic transmissions.

    “Semi” truck transmissions usually provide at least nine or ten gear ratios, but possibly as many as eighteen (e.g. Australian road trains). A large number of transmission ratios means the internal combustion engine itself can operate within a narrow range of speeds. The range of speeds over which an engine is expected to perform well has implications for the design — the narrower the range, the more the engine can be optimised for that range. Also, having so many gears allows fine-grained control of engine braking for better control on downhills and in curves.

    A ten speed manual transmission is controlled via a six-slot H-box pattern, similar to that in five-speed cars — five forward and one reverse gear. Gears six to ten (and high speed reverse) are accessed by toggling a selector control for the range change low/high, so that first gear becomes sixth, second becomes seventh, etc.

    Another difference between semi-trucks and cars is the way the clutch is set up. On a automobile, the clutch pedal is depressed full stroke to the floor for every gear shift to ensure the gearbox is disengaged from the engine. On a semi-truck with constant mesh transmission (non synchronized), such as by the Eaton Roadranger series, not only is double clutching required, but a clutch brake is required as well. The clutch brake stops the rotation of the gears, and allows the truck to be put into gear without grinding when stationary. The bottom of the clutch pedal stroke is where the clutch brake activates and as a result only partial or “half” clutch pedal stroke is used when a vehicle is in motion.

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