6l80e swap questions

[kbomhower]

i got a 99 gmc sierra and swaped to used 4l80e... now reverse went and im not sure what to do. wondering if id be worth it to swap to a 6 speed 6l80e. whats involved in the swap since already am setup to run the 4l80e?? and would i gain by doing it or better off rebuilding the 80e i have and beef it up some? thanks for the input

[blacstar]

I would rebuild what u have. engine mods?

[Frenchy]

Not a direct swap. At all. Mechanically, yes. Electrical, no. From what I've read you'd basically have to run a GMT 900 engine harness PCM & TCM for the 6l80e, running stand alone, along with your trucks factory harness and PCM to run interference between the stand-alone, and your BCM, gauges, A/C etc. Sure it could be done, but I wouldn't want to do it.