If you are going to run a metal spur, you need hardened pinions. A non hardened one, will last about ten minutes before all the teeth are gone.
Or you can use non hardened on a nylon spur.
Losi LOSA3562 45T Spur Gear Plastic 8ight E 2.0 8ight E 4wd
All the losi 8 variants interchange.
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