Does anybody know if a 3.9 trans housing will fit on a 3.8 trans 06 monte to an 02 monte

 

They are the same transmission. I believe the gearing is different though, and I would think it's electronically programed different that the 02 tranny. I doubt it would be a "bolt in play," but I am pretty sure it would bolt up to the 3.8, just not sure about the function with the PCM.

 

I discussed this exact subject with Will at Overkill. He told me that the 3.9 transmission has different gearing (more performance related according to him). He said it would require a PCM reprogram.

 

my question is the 3.5 and the 3.9 has a pcm and a tcm. the tcm is just for the trans because it is electrical thats what i was told by a tech. the pcm and tcm talk together to have the shift and cruse to be smoth. what i mean is what i was told the tcm telles the silinoids to stay where there at when your going a sertain speed, and the tcm pickes it up and tells the pcm and tcm when there is no set amount of rpm or vise versa when slowing down. thats what i was told. the pcm and the tcm has to be on the same page for the normal operation.

 

So I cracked the housing on my 3.8 I ordered a 3.8 they sent me a 3.9 trans so I just wanna make sure that I can take that house from the 3.9 an put it to my 3.8 an keep it moving