This is a Cummins ISX / ISX15 / X15 Crankshaft Hub Puller. 
This puller bolts up easily to the existing hub on the crankshaft and will pull the hub off the crankshaft without damaging the hub or crank. 
You will need a 2-5/16” socket and a 1” drive impact. I used my 1” drive Milwaukee impact and from start to finish I had the hub off in less than 5 minutes. 
No heat required, although I would recommend a small amount of heat to make pulling it off easier. 
Can be done In chassis, which avoids Cummins Quickserve way of getting the hub off by drilling / grinding/ splitting the hub. 
If interested I can send you a quick video to show the process. 
You will be amazed at how quick and easy this tool pulls the hub off., enabling you to re-use the hub after fixing the bad gears. 
Feel free to contact me at 1-616-318-0526