Good morning, There is always the posibility of a mismatch of parts. From your post, the old starter could have damaged the ring gear. If this car has a history of no problems and then a failed part, the part or something related should be checked out. By something related I mean the electrical system. The system of cables and connections needs to be checked for voltage drops between the battery positive terminal and the starter + terminal and the negative battery terminal to the starter case and both checks when cranking. Checking with an ohmmeter is useless. Battery condition needs to be checked with a load pile, a hydrometer and a micro processor capacitance tester and all this is what auto electric specialty shops generally do quite well. There is also the possibility that there is something going on called installer error. Basic engine timing might well be a factor. This can be checked by disabling the ignition and cranking the engine BTW. From many years of experiences, I will say that rebuilt parts from a lot of sources should be high on the list of possible causes also. Warren Anderson Sedona,AZ [Non-text portions of this message have been removed] ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to http://autos.groups.yahoo.com/group/Chrysler300/join and select the "Leave Group" button For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylangYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: Chrysler300-digest@xxxxxxxxxxxxxxx Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/