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Dodge 4x4 Cummins Diesel Automatic to Manual Conversion Information
NV4500 and NV5600 Conversions on 1989-2002 Dodge 4x4 originally equipped with automatic transmissions. This is not quite so simple as it sounds because of transfer case incompatibility. For all trucks with NP205 transfer cases and most newer models with NP241 transfer cases, the transfer case input shaft is only a 23 spline and the manual transmissions have a 29 spline output shaft.
With the NV4500, you can install a Torque King 23 spline output shaft although this is not as strong as the 29 spline shaft. The best option is to install a 29 spline input shaft in the transfer case. This is pretty straight forward with the NP241, however it is not so simple with the NP205 found in 1989-1993 trucks. For these models, the bores for the input bearing and transfer case adapter must be enlarged by a machine shop to accept a larger bearing and seal, plus you will need to get a 29 spline female coupler shaft to join the transmission output shaft to the transfer case input shaft. Our QK2001 has the pieces required to convert your 23 spline NP205 to 29 spline.
In addition to the transfer case modifications, you will need a new flywheel, flywheel bolts, clutch assembly, clutch bolts, bellhousing (NV4500 only), clutch fork, clutch hydraulic system, clutch pedal, brake pedal, transmission mount, transfer case linkage, and hardware. You will need to cut the cab floor/carpet to accept the shift tower, rewire the backup lights and cruise control. In most cases you will also need to have driveline modifications done. Some models will also require crossmember relocation. NV5600 conversions in 1989-1993 trucks will also need a new flywheel housing. and custom starter as will first gen trucks using 1994 and newer bellhousings.
Unless you have a donor truck to cannibalize most or all the parts from, this is one expensive conversion. NV4500 conversions will run $6,000-$7,000 for all new parts and NV5600 conversions are even more expensive.