4l80e

ok i heard that the 1991 c3500 came with that trans.. I have a 89 tpi . what would i need to run that trans/setup?? Does anyone have a sysetmatic on the wire haress 4 a 91

I think you would need to get a stand alone computer that would run the trans. They aren't cheap but I think it's a good way to go.

im thinking if i found a 91 harness everthing will plug and play

i think in 91 the 4l80e was only mated to the 6.2 deisel, i could be wrong.

ok hers the scoop for a guy that been doing this for 20 years i finaly get to help a felow mimber woohoo


ok if your truck has a 4l60e in it a 4l80e will run with the exsisting puter

if not the best bet is to get a stand alone

you can find the stock harness but thar hard to get runing lots od wires to splice

i have the tci stand alone on my truck, works really good. its fully programmable for shift points, line pressure ect.