The prerunners are built off the 4x4 chassis, using the same suspension/hubs/brakes. All heavy duty stuff. If you want to pull something heavy the prerunner is going to be better suited to pull it then the reg height tacoma. Also if you want a v6 you have to get the prerunner(or an Srunner or Xrunner

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The prerunners although not 4wd are very capable off road and it's the perfect truck for those that rarely ever need 4x4 but go offroad once in a while. Also you save on gas and insurance costs, as well as maintenance and service.