Hi Ron, That is exactly the issue that I'm trying to drive out. We have many anecdotal examples of folks using Dexron for 100k, 200k and even 300k miles in their transmissions with no issues, including some letter cars. Yet we have evidence (particularly if someone has a copy of the actual tech bulletin) that Chrysler at some point specified type F, at least for letter cars. We know that type F provides firmer shifts. We also know from 40+ years of club experience that letter car transmissions in fact did fail prematurely when not rebuilt to 300 letter car specs and when certain fluids were used, at least in severe duty use. For drivers that just go to the local cruise in and only put a couple hundred miles (or less) on their letter car a year, perhaps the whole issue is mute. The non-letter car transmissions, such as the 300 Sport, were not built to the 300 letter car specs and perhaps it is less critical to use type F unless firmer shifts are desired?? Don Verity is one of our current transmission experts, perhaps he has some advice? 300ly, Carl Bilter _____ From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of Ron Waters Sent: Thursday, May 17, 2012 6:32 AM To: Chrysler300@xxxxxxxxxxxxxxx Subject: Re: [Chrysler300] Dexron vs. type F So is type F just for heavy duty torqueflites, such as the ones behind our letter cars ? Or can/should it be used in all torqueflites, including the one behind the 318 in my 58 Plymouth ? Ron [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/