Since all the 2003 boys are getting good mpg, maybe due to the lower hp as well as no 3rd injection cycle, has anyone ever thought of changing out the 2004.5 ECU and replacing with a 2003 ECU in a truck with an automatic trans?

I am assuming both trucks would have the 48RE transmission.

Please let me know if anyone has thought of this as well?

 

believe the trannies are different plus the hrsepower

 

I'm hoping that someone more knowledgeable than I will chime in on this. I'd gladly go from 325/610 to 305/555 for better mileage.

 

Well im far from more knowledgeable But I dont think it wouldnt work considering the 3rd injection and also the electronic wastegate on the 04.5's and up. I think something would get messed up.

 

the 2003 ecm can not work in an 2004.5 period

 

And you can not get any more knowledgeable than Mr Wagner in regards to the matter of ECM's!

 

True statement. I wonder though, if it's possible to program the 2004.5 ECU so it does away with the 3rd injection event. Maybe a special Smarty program?

 

The newer ECM performs many additional tasks and has gobs more memory.

Pete

 

Agreed , ask Bhaner, he tried an 04.5 in an 03?, Trying to get the 3rd injection event I believe.