Self-propelled mowers can make the job of mowing easier. Pulleys and gears connect the engine with the wheels making the self-propelled mower easier to push. Self-propelled mowers are either front wheel or rear wheel drive. Front wheel, self-propelled mowers pull the mower forward so you have to have more control over your mower if you want to go in a straight line. Rear wheel mowers are more inclined to go straight.