the cummins/V10 518/618 is running behind viper motors in jeeps----infact jeep guys in the know that run corvette 5.7 motors are running the built 904,s that came out the old postal jeeps because they are stronger than the chev 350/400 offerings----the 618 will give you 5-6 pinion sun gears and the overdrive is packed with extra clutches with a straight gear apply----bob