08 to 03 Silverado tranny swap

[bart06]

Im trying to put an 08 tranny in my 2003 Silverado I read a forum that said that the plugs are the same just the extra connectors for the iss if my Tcm isn?t looking for the iss will I still have issues with torque converter lock up? I?ve heard that you can just plug it in and it?ll work and I?ve heard that you?ll have shift issues and lock up issue just looking for some foresight, thanks

[TransGo Robert]

Im trying to put an 08 tranny in my 2003 Silverado I read a forum that said that the plugs are the same just the extra connectors for the iss if my Tcm isn?t looking for the iss will I still have issues with torque converter lock up? I?ve heard that you can just plug it in and it?ll work and I?ve heard that you?ll have shift issues and lock up issue just looking for some foresight, thanks

It will work just fine. The other way around is what causes issues.

[Pitbull]

I did a swap similar to this, the only difference I had was the turbine speed sensor in the front pump housing on the later model trans didn't get used. Truck still goes hard 3 years later. Just make sure you clean out the cooler lines good, then extra good, then do it again....