Hey I have a 03 chevy 1500 4x4 extended cab. The trans is shot. Ive found a 99 Chevy 2500hd regular cab thats been wrecked for a good price. Would i be able to use the parts from that truck to swap in the 4l80 in place of my 4l60? Thanks in advance

 

You can but I am not sure about the mounting. I know the 4l80 is larger and the wiring harness is different. You can buy an adapter harness or a new plug end and re-pin/add wires. You will also need to do something with the driveshaft as it will be a different yoke from the 80 and need to be shortened. Doable but not without spending money above the purchase of the 2500.