LexusPartsNow.com offers the wholesale prices for genuine 2015 Lexus IS250 Base parts. Parts like Partial Engine Assembly are shipped directly from authorized Lexus dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 4 Cyl 2.0L, 6 Cyl 2.5L, 6 Cyl 3.5L. Trim: LUX.