trying to fix the rear driver side sag which is about 1inch currently. Had the truck a couple months now and previous owner never mentioned it had airbags in the springs which I just found when I seen some air fittings under bumper. I was planning on putting some Ome springs in the back. Is that enough to hopefully level out back end since I'm assuming they are original. One of airbags is not holding air so I thought I would just remove them. Don't tow anything and other than camping gear no weight in the back end either or should I replace airbags as well? Thanks