17 powertrain into 03 tahoe

[jaywoo65]

I think you'd be better off selling the 17 (parting it out or selling whole) and getting a freshly rebuilt longblock for the 03. Maybe even a 6.0 with a cam/longtubes/tune.

 

[UrbanSuburban]

While the 17 does have Can Bus, it also does have OBD2 protocols as well, that has not changed. The systems all communicate a different way than the 03. One of the big new things to come will be OBD3 which is supposed to send your regional DOT a info packet that your vehicle is not compliant and you would get a summons to have it fixed. Big Brother anyone....