About the only way to correct the sag is to go with some new coils - I installed the OME 891 on mine to correct the problem and they give a very firm ride, or you can go with the 890 for a less firm ride, just depends on if you are towing or carrying heavy loads. If you go that route, and have the extra money, I would recommend replacing the shocks at the same time, that is if they are shot and need replacing. Good luck.