I'm looking to do a Cummins swap into my 98 Ram 2500. It has the NV4500 in it now but it has the 1-1/8" input shaft. I want to switch it to a 1-1/4" shaft. What all is required to swap the shaft? I found a new one on eBay that is a 10-spline for around $100. Are all of the shafts the same splines? Do I need anything other than the shaft? Does anyone know the procedure to do the swap?

Thanks,
Ross

 

You need to know the correct tooth count for 4th gear (the gear on the input shaft). Take the front retainer out and the top cover. You might be able to sneak it in, but you may have to take the tail shaft off and disassmeble the end to move the shaft back enough.

 

Will I need a new retainer and bearings for the larger shaft?

 

yeap.

 

Does anyone know if there is such a thing as a 1-1/4 input shaft kit? All I have found is the kit for 1-3/8" and I don't really want to spend that much money for it.