If you can get the dorman LCA police/Taxi for the 04 Chevy Impala, I would get them, if they will fit. I use the 01 Chevy Impala Police/Taxi LCA on my 01 GP. I also use the 01 Impala Police/Taxi Struts at all 4 wheels which are superior to the OEM Delco struts and the KYB's which are junk....