Around 200, I began looking in stores and online for air struts, if such a thing existed. Having had air SHOCKS on 2 previous cars, I was hoping I could also beef up the rear suspension on my 1996 Buick Regal which uses rear STRUTS. Back then I began to realise that there were no such things as air struts. I’m hoping that by now, with more cars using struts for the rear suspension rather than shocks, strut manufacturers may have started making air struts if such a thing is possible. Anybody ever seen air STRUTS anywhere?
Haven’t seen any yet. You might try some new springs or lightening the load in the trunk, or both.