Chrysler 604 (sort of off topic)

Brian,

I also posted recently on a T&C A604 rebuild, since keeping me from moving forward on the Dart. My real need was to replace the flex-plate (hope you changed that, read my post), but did the tranny to be safe and found it perfect inside. Currently, I am fixing an A413 in my son's Voyager (never ends).

I wouldn't use mineral spirits, unless you read that is a common procedure. It could attack rubber seals. When you refill, look for synthetic ATF+4. I noticed that the Autozone brand is also synthetic, so maybe from the same plant as the over-priced brands.

BTW, much discussion on what ATF to use in our old 904 and 727 transmissions. Original was "suffix A" since only other choice then was "Type F" (mostly Fords). I have used Type F because I read it had more friction modifiers. Standard suggestion is Dexron III, but recently I read that ATF+4 has even more friction (less slip and shudder). For A404/413/604 (same as older Torqflites), some recommend Dexron III, but I also read to use ATF+4. I does cost a bit more, but take no chances with a tranny.