more than likely you have blown out air bladders that surround your rear shocks. It’s a standard shock filled with hydraulic fluid, with a rubber air bladder around it that can fill up with more pressure as the ride height sensors detect more load being placed in the rear of the SUV. Depending on how long one or both bladders have been torn, the air compressor that fills the bladders will likely be burnt out as well. It’s a very well documented topic. I’d highly suggest using the search feature specifically searching through the 2000-2006 section of the forum within the street suspension subforum of that section. There’s tons of threads already discussing all the options available for tackling this very issue. There’s tons of talk on which route to go to fix this issue based on what purposes you’re using the vehicle for. These threads also contain links or mentions of what you’ll parts you will want to purchase based on how you want to handle fixing it.