So tires and rims for sure. And we have Springworks up where I live that's all they do is custom spring work.. Question on the springs though. The unit im looking at is 2874 Dry weight with gen and water/gear most likely 3200-4000max but definatly now any where near 4500 pounds if the springs are rated for 6K weight I still have some room to grow right? maybe add airbags to help ride? the springs only really have the weight of the bed as it sits on the driveway. is there really any need for springwork to be done?