Automotive City in Grass Valley now offers the JASPER Re-manufactured Nissan VQ40DE 4.0L DOHC Engine! Jasper Engines & Transmissions, the nation’s leader in remanufactured products, announces the availability of its re-manufactured Nissan VQ40DE 4.0L engine. This DOHC V6 engine is available in exchange for the following 2006-2011 vehicles: Nissan Frontier, Pathfinder, X-terra offering several advantages: