. . "5T final gear)These gearboxes are used in a LOT of vehicles, especially older ones.#3A - Older Bigfoot's/F150's, Junior Jeeps (one wheel drive), Lamborghini's, Corvette's, etc.#3B - Newer Bigfoot's/F150's, Quads (Kawasaki Ninja), Firerock's, Wild Thing, etc.There are definitely some 12 volt models that use a #3 gearbox, but if it is 6 volt, it is most likely a #3 gearbox.If it is a Super 6 vehicle," . .