LexusPartsNow.com offers the wholesale prices for genuine 2000 Lexus GS400 parts. Parts like Rear Seat & Seat Track are shipped directly from authorized Lexus dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 6 Cyl 3.0L, 8 Cyl 4.0L, 8 Cyl 4.3L.