Owen is correct. Per page F-21 of the dealer album description updated on January 3, 1957, the Optional Chassis and Engine package included High -speed camshaft, 10:1 compression ratio, limited slip differential, 2 1/2" low back pressure exhaust system, heavy duty clutch and drive shaft, manual transmission, and manual steering. This package is not recommended for the average 300C customer because of poor low end performance and rough idle. Jim Bartuska Niles, Mich w/COLD, Windy Snow Showers In a message dated 12/9/2009 9:15:51 P.M. Eastern Standard Time, ram300@xxxxxxxxxx writes: It was part of the optional "chassis package" on the '57 300C but it was not named Suregrip until 1958. I have heard rumors that some of Kiekhaefer race 300B's had limited slips though...... Owen -----Original Message----- From: _Chrysler300@Chrysler300@Chr_ (mailto:Chrysler300@xxxxxxxxxxxxxxx) [mailto:_Chrysler300@Chrysler300@Chr_ (mailto:Chrysler300@xxxxxxxxxxxxxxx) ] On Behalf Of Terry & Andree Hoeman Sent: Thursday, 10 December 2009 1:48 p.m. To: _chrysler300@chrysler300@chr_ (mailto:chrysler300@xxxxxxxxxxxxxxx) Subject: [Chrysler300] when did limited slip differentials begin A friend just asked if I knew when limited slip differentials started on Mopars. Anyone have any knowledge?? I'm thinking later 50's but no way certain. ------------------------------------ To send a message to this group, send an email to: _Chrysler300@Chrysler300@Chr_ (mailto:Chrysler300@xxxxxxxxxxxxxxx) For list server instructions, go to _http://www.chryslerhttp://www.chttp://wwwhttp://w_ (http://www.chrysler300club.com/yahoolist/inst.htm) For archives go to _http://www.forwardlhttp://www.fhttp://www.fo_ (http://www.forwardlook.net/300-archive/Yahoo) ! Groups Links [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: 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/