If you have a low mileage GNX .and don't drive it much ,I would keep the OEM shocks on. I had that same decision about 7 years ago
at 30000 miles ,I remove the OEM shocks and replace them with a set Bilsteins because I do drive my Buick about 1200 miles a year.
I do still have my OEM shocks for future reference. But if do decide to change the shocks out, you sure will be able to tell the different
in the ride and handling. There are lots of aftermarket shocks, but I'm kinda partial to Bilstein.
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