Nissan Repair: Distributor for Nissan, distributor shaft, nissan frontier

Question
I have a 1999 Nissan Frontier 4x4 automatic with a v 6 engine.  The truck stopped running and the mechanic at the Nissan shop said it was the distributor gone bad.  He replaced the distributor and now the truck is running but it makes a horrible knocking or grinding sound in the distributor area.  The mechanic said it was the results of placing a new distributor gear against an old gear on tha cam shaft.  The truck made no grinding or knocking before the distributor change.  The service manager said the mechanic should have switched the gear from the old distributor to the new before he installed the new distributor, however, it was too late because he turned in it for a core. Now the service manager says he will obtain a used distributor from the junk yard and change the gears on the distributor shaft and it should quieten down a lot.

My question, will it help to change the gear on the new distributor for a used gear from the junk yard?  Question 2 will it hurt the engine to continue to run it as it is.  The sevice manager say the gears will wear in and the noise will go away.  After about 3 weeks and a thousand miles I cannot tell the difference.  What do you suggest?

Thank You

Answer
Billy,

Yes, to both counts.  The new gear on an old cam sometimes makes noise.  Yes, it will eventually wear in.  Or, you could get a used gear and replace the one on the new distributor and expedite the process to get the noise to quiet down.  Either one is a viable solution and it is your choice.  If the dealership will do the work for free let them do the change of the gear and be done with it if the noise is so bothersome.