i keep destroying spurs within 10 min. please help!

[JERRY2KONE]

That rig looks pretty used. Did you doublecheck to see if everything rolls easily before hooking up the spur and pinion gears? You need to make sure that the center diff or tranny rolls freely, and all of the CVD's trun without any restrictions of any kind. Even with everything hooked up in my trucks I can spin my wheels with one finger and turn the motor in both first and second gear. The pitch of the gears is critical. They have to match exactly, and from what you described something in your setup is not right. A lot of guys run a metal pinion gear and plastic spur without any troubles. I run all metal gears in my setups, and put a small amount of Aqua grease on things to keep the noise levels down. If you get everything just right it is smooth and quiet. You might want a seasoned vet to have a look at your setup.