Lot of good advice already given. You can crank up the torsion bars pretty simply by yourself. No dealer required for this. As mentioned, if you only crank up the torsion bars your ride will suffer, and ball joints and CV axles will be at unnatural angles compared to where they should be causing faster wear. You can also do the same thing without having your ride suffer by replacing the torsion keys. This will still raise the truck without stiffening up your suspension. Either way you go you should get a front end alignment. Also, if you go the route of new torsion keys, they generally come with brackets for extending your factory shocks.