After checking the part # on my 3:23 unit, it is 2070742, with a small 's' below the number. Is this a sure grip? I can see gears and cross shafts. The other unit is 2881489, with a '9' on the opposite side. This unit has springs visible, and the ratio is 3:55 to 1. This is a sure grip unit of some kind. It has 21 bolts on the ring gear. I assume this is not the correct diff. for the K. If the 742 is a conventional rear and not a sure grip, can the center drum from the 489 be intsalled in the 742, or should I seek a 742 for real sure grip? Dave --------------------------------- Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. [Non-text portions of this message have been removed] To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/ Yahoo! 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: mailto:Chrysler300-digest@xxxxxxxxxxxxxxx mailto: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/