4l60-E

[1993blazerlt]

how hard would it be to swap a 94 tranny into an 89 blazer? Is it just the wiring that is the largest concern?

[Matt 4.3 TBI]

You'll need a tranny controller for the 4L60E, as the older computers have no provisions for this. GM sells one, but it's pricey:
Part # 12497316 4L60E Transmission Controller $1190.26

I haven't heard much about this one: http://www.powertraincontrolsolutions.com/content-4.html but it's definitely cheaper.

[Matt 4.3 TBI]

Quick addition: www.gmpartsdirect.com sells the controller for $851.

[1993blazerlt]

i have a complete 94 blazer with the computer and wires how hard is it to swap a wiring harness

[bvr775]

tci sells one too