Avoid them. The Northstar motor is beset by a host of issues. Starving themselves of oil being one of the best. Air suspension always fails, just a matter of time.
Fun car, great acceleration, great ride, great big money pit. I kept an STS for almost a year, got out of it with only minor issues, but the car self destructed 6 months after I sold it. I purchased it with 80k on the clock, and 40k on the replacement engine.

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On some nights I still believe that a car with the fuel gauge on empty can run about fifty more miles if you have the right music very loud on the radio. - HST

1983 300SD - 305000
1984 Toyota Landcruiser - 190000
1994 GMC Jimmy - 203000

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