I'm going to get a new/used 2wd RCSB and put a new 6.0L with a 4l80E tranny in. What type of engine and transmission should the truck already have? I'm guessing the 4.8-5.3l with the 4-speed tranny, would the 4.3l with manual work? I'm looking to spend about 35-40k on the truck, but i want the truck to no more than 20k. Thanks for the help.

 

Get it with the 4.8 auto. You'll have an easier time finding that truck and it will cost you less. The 4.8 will have the PCM and all necessary harnesses to bolt in a 6.0 motor. The 4L80E may be a little different. You will need to get custom programming to run that tranny and may have to change some mounts. Otherwise, the 6.0 would be a direct drop in swap.