Yes, just depending on your drivetrain, it could be slow and get horrible gas mileage. or it could be some what decent, but putting bigger tires will affect gas mileage and power and torque. Being a Sahara, you should have the 4.0, so do you have an auto or standard trans? and what rear axle do you have? If you have an auto you more than likely have 3.55 gears which you should be ok, but again gas mileage wont be that great and getting up to speed might take a while on the highway. If you have a standard trans, then you should have either 3.07 or 3.73s, if you have 3.73s, you wont really have any issues, if you have 3.07s, its going to be a dog to get it up to speed on the highway, but itll manage. In any case, regearing would help to save gas mileage and have it to be able to drive like if it were factory, but it is not a neccesity for 33s.