Picked up an 03 ECSB silverado with a 5.3 and 4l60e about a month ago. Since then, I have been collecting parts to start a build. I threw on an intake, cat back and an EFI tune. Hit the track last night to get a base line of what it will do and the progress it makes.

My local 1/4 mile track (Salt Lake City) is at 4300' and last night was roughly 6700' DA. I launched it 4x4 and clicked off a miserable 2.6 60' and pounded out an earth rotating 16.9@83mph pass. The truck feels MUCH better on the street when I dont need to mash it off the line. I don't think it could have been any worse, so it should be nothing but improvements from here. It needs rpm off the line soooo bad.

I picked up a 4l80e, shift kit, 3200 stall converter, tru cool 40k cooler and all the necessary swap parts that are needed. I plan to start the swap this coming week, or possibly even tonight when I get off work.

I already did the shift kit and put new seals in the trans. I also already ran the ISS harness to the PCM while I installed the electric fans last week. I've got tunes set aside that I will segment swap as well.

Future plans are to be around 500whp, nothing crazy, but will still move out.

 

I got the 4l80e swapped in and running. Tested in 4x4 while I wait for my new rear driveshaft, which I should have tomorrow. I can't wait to drive it.

 

What input shaft prat number did you use for the 4l80 input swap?

 

Are you referring to the transfer input shaft?

This is the part I bought. I would steer clear of the cheap knock off ones.

Transfer Case Input Shaft NP236 NP241 NP243 NP246 32 Spline with Pocket Bearing | eBay

 

i definitely want to stay away form the knock off ones, but I need one for the 261 transfer case, what transfer case do you have?

 

Mine is the np246.

 

Take pics if possible on the swap! This is something I want to do as well in the future on my 01 5.3 single cab and this is going to help out a lot! Keep us posted.

 

There's several stickies in the gm drivetrain and suspension section as well.

 

My swap is complete. I finished it yesterday. I didn't take any pics since there are already several detailed threads about the swap.