I'm putting a 2004 4L60e behind a 5.3 in my s10. I've got a nice converter that came out of my 93 fbody 4L60 trans that I'd like to use. I'm aware that I may need a pilot spacer depending on the flexplate and that I may need to elongate the bolt holes, but a friend told me that the 2004+ 4L60e's have a different pump and the older converters won't work. I searched this and couldn't find anything, but I did find that the 4L80e used a different pump in 2004+. Is my buddy just confusing his transmissions? Should my older converter work in the 2004 trans?

 

All 1997 or earlier 4L60E have a 298mm input shaft and matching converter.
All (except for Vette) 1998 and later 4L60E for V8 engines (e.g. LS1, LS2) have a completely different 300mm input shaft and therefore a different converter.
1998+ 4L60E for V6 engines still use the 298mm input shaft. I've posted this picture a bunch of times, but here it is again:



In short, if the your 2004 4L60E has the 300mm input shaft (e.g. it came from a V8 vehicle), which is what you want for an LS engine, your old converter will NOT fit.

 

Bummer, looks like I'm converter shopping. Thanks for clarifying.