(2 pcs) K1 Max Extruder Gears Upgrade Kit All Metal Filament Drive Extruder Gear for Creality K1,K1 Max K1C Motor Nickel Plated Hardened Steel Plating 3D Printer Accessories Replacement Parts

Get full-metal replacement gears that fit in the stock extruder. The plastic gears in my extruder didn't lose any teeth, but I still wanted something more durable. Since then I have not had any issues with the stock extruder. It is a very inexpensive upgrade too. I bought these: Filament Drive Gears Reduction Gear Bonus: If you want an upgraded extruder motor with more torque you can go with this one. I only got it because one of the wires pulled out of the stock motor. Beside having higher torque, the upgraded stepper motor has a more robust attachment for the wires. Just make sure you take the yellow gasket off the old stepper and put it on the new one.