Unity automotive has over 50 years of experience manufacturing parts in the aftermarket automotive industry. The company offers superior quality, specializing in making rock solid auto parts that withstand the test of time. With a true understanding of their marketplace they have become the industry leader in innovation of aftermarket suspension. Unity automotive delivers top of the line quality suspension parts made to insure a trouble-free installation and long-lasting reliability. The Elite Suspension Line Powered by Unity introduces solutions to retrofit steel springs converting your air ride to a more reliable passive suspension setup. 1997-2002 Ford Expedition, 1998-2002 Lincoln Navigator NOTE: Excludes 4WD Models