One night on a trip back to Las Vegas from the Inland Empire in California, driving up the El Cajon Pass, for some reason my (then) wife put her hand on the knob of the gear shifter in our Mazda truck. It was in a lower gear, because that road is really steep, and it requires lower gears for enough power to pull a vehicle up that grade. I saw her slip her panties off, as she gave me a strange look and a smile. She turned her body around in the seat, straddled the shifter, and moved so her pussy was directly over it. Bracing herself on the seat back, she reached down with her left hand, and maneuvered the shift knob to her pussy, spreading her labia to receive the rather large ball. Once she got herself in position, she put both hands on the seat back, and began to gyrate her hips, pressing down on the shifter. Her skirt was way up over her waist, and there was just enough ambient light that I could see what she was doing. (I DID have to focus on driving, though. Rats!) She kept applying pressure on the shifter and it slowly eased up inside her until the entire ball was in her pussy. She moaned in pleasure, occasionally glancing at me to make sure I was enjoying her show. She rode the shifter all the way up the highway to the high desert, coming with a typically beautiful "woman song" of pleasure as her body spasmed over and over again. Those transmission vibrations really did a great job on her, and I was thankful for her thoughtfulness. She must have known I had often fantasized about her doing that, and the time and place were just right! What wonderful memory!