<P> There was a total of 5 transfer cases for the four - wheel - drive Ram . All are part - time and have a low range of 2.72: 1 . The 1500 featured a NP231 and NP231HD . The NP241 was standard on V8 2500 Rams . The 2500 and 3500 V10 and diesel featured a NP241DLD from 1993 to 1997 . In 1997 the NP241DHD became an option for 2500 Rams and was standard on 3500 Rams from 1998 to 2002 . </P> <P> The Dodge Ram features a wide variety of axles . For the front axle of 4x4 Rams, a Dana 44 was used on all 1500 Rams and the early (light - duty) 2500 Rams . However, most of the 2500 and all 3500 Rams use Dana 60 front axles . The 1500 Rams and some early light duty 2500 Rams used a 9.25 Chrysler (Spicer) axle in the rear . A Dana 60 rear axle was used on heavy duty 2500 V8 Rams . A Dana 70 rear axle was used in 2500 Rams with a V10 or a Diesel / Automatic transmission combination . A Dana 80 rear axle was used on 2500 Rams with a manual transmission and V10 / diesel engine combination . Every 3500 Ram was made with a Dana 80 . The front drive axles in these Rams were unique in the fact they didn't feature Locking hubs, but featured a Center axle disconnect . The 2002 2500 and 3500 Rams saw the eventual phase out of the Center axle disconnect, in favor of front axles that were permanently locked in . Dodge continued to feature front axles like this for their 2500, 3500, 4500, and 5500 trucks until 2013 models . </P> <P> A natural - gas - powered engine debuted for 1995 but was not popular and was only used in fleet vehicles on a very limited production run . The Cummins B Series engine was switched from the 12 - valve to the 24 - valve (ISB) version in the middle of the 1998 model - year Dodge Rams due to emissions regulations . The ISB featured a new computer - controlled injection pump, 24 - valve head design, and an electric fuel pump . </P> <Table> <Tr> <Th> Years </Th> <Th> Engine </Th> <Th> Power </Th> <Th> Torque </Th> <Th> 8th VIN </Th> </Tr> <Tr> <Td> 1994--2001 </Td> <Td> 3.9 L (239 cu in) Magnum V6 </Td> <Td> 175 hp (130 kW) </Td> <Td> 225 lb ⋅ ft (305 N ⋅ m) </Td> <Td> X </Td> </Tr> <Tr> <Td> 1994--2001 </Td> <Td> 5.2 L (318 cu in) Magnum V8 </Td> <Td> 230 hp (170 kW) </Td> <Td> 295 lb ⋅ ft (400 N ⋅ m) </Td> <Td> Y </Td> </Tr> <Tr> <Td> 1995--1997 </Td> <Td> 5.2 L (318 cu in) Natural Gas V8 </Td> <Td> 200 hp (150 kW) </Td> <Td> 430 lb ⋅ ft (580 N ⋅ m) </Td> <Td> </Td> </Tr> <Tr> <Td> 1994--1997 </Td> <Td> 5.9 L (360 cu in) Magnum V8 </Td> <Td> 230 hp (170 kW) </Td> <Td> 325 lb ⋅ ft (441 N ⋅ m) </Td> <Td> Z (5 for the heavy - duty version) </Td> </Tr> <Tr> <Td> 1998--2002 </Td> <Td> 5.9 L (360 cu in) Magnum V8 </Td> <Td> 245 hp (183 kW) </Td> <Td> 335 lb ⋅ ft (454 N ⋅ m) </Td> <Td> Z (5 for the heavy - duty version) </Td> </Tr> <Tr> <Td> 1994--2002 </Td> <Td> 8.0 L (488 cu in) Magnum V10 engine </Td> <Td> 300 hp (220 kW) </Td> <Td> 450 lb ⋅ ft (610 N ⋅ m) </Td> <Td> </Td> </Tr> <Tr> <Td> 1994--1995 </Td> <Td> 5,883 cc (5.883 L; 359.0 cu in) Cummins 12 - valve diesel I6 </Td> <Td> 175 hp (130 kW) (manual), 160 hp (120 kW) (auto) </Td> <Td> 420 lb ⋅ ft (570 N ⋅ m) (manual), 400 lb ⋅ ft (540 N ⋅ m) (auto) </Td> <Td> </Td> </Tr> <Tr> <Td> 1996--1998 </Td> <Td> 5,883 cc (5.883 L; 359.0 cu in) Cummins 12 - valve diesel I6 </Td> <Td> 215 hp (160 kW) (manual), 180 hp (130 kW) (auto) </Td> <Td> 440 lb ⋅ ft (600 N ⋅ m) (manual), 420 lb ⋅ ft (570 N ⋅ m) (auto) </Td> <Td> </Td> </Tr> <Tr> <Td> 1998--2000 </Td> <Td> 5,883 cc (5.883 L; 359.0 cu in) Cummins ISB 24 - valve diesel I6 </Td> <Td> 235 hp (175 kW) (manual), 215 hp (160 kW) (auto) </Td> <Td> 460 lb ⋅ ft (620 N ⋅ m) (manual), 420 lb ⋅ ft (570 N ⋅ m) (auto) </Td> <Td> 6 </Td> </Tr> <Tr> <Td> 2001--2002 </Td> <Td> 5,883 cc (5.883 L; 359.0 cu in) Cummins ISB 24 - valve diesel I6 </Td> <Td> 235 hp (175 kW) (5 - speed manual or automatic) </Td> <Td> 460 lb ⋅ ft (620 N ⋅ m) (5 - speed manual or automatic), </Td> <Td> 6 </Td> </Tr> <Tr> <Td> 2001--2002 </Td> <Td> 5,883 cc (5.883 L; 359.0 cu in) Cummins ISB 24 - valve diesel I6 </Td> <Td> 245 hp (183 kW) (High Output) </Td> <Td> 505 lb ⋅ ft (685 N ⋅ m) (High Output) </Td> <Td> C or 7 </Td> </Tr> </Table>

When did dodge go to the 24 valve