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How to adjust seating to the proper position while driving
Slide your seat until your knees are slightly bent when you're pressing the gas.
Move your seat forward if your legs are completely extended when you press the gas pedal. Move your seat back if your legs are bent too much.
Keeping your knees slightly bent while you drive will prevent knee pain. Sit so there's a gap 2 fingers wide between the back of your knee and the seat.