If ya post the part number folks might be able to help? Anyhow my aspect came with them and they are not so much to raise the rear end as to provide a stable ride. Mine wandered all over until I figured out what air to run in them then it became more manageable. When we got it it had no air and was terrible to drive. My pick up is just like what your was. Yes you could lift the rear with air pressure but again it was just to keep level more than anything.
How does the rig handle at various pressures? what are you trying to accomplish with them is another question. Too much air too harsh a ride, too little and it is mushy right? I tune around 55-65 psi and yes it sometimes drags its rear over speed bumps curbs but less so at the psi I indicated. it weighs in around 13K and we tow a small car behind.
