I have an 04 SS silverado with a 4L65E in it. Its been rebuilt once just with upgraded clutches, heavy duty band, and shift kit. I recently switched superchargers and put a D1SC ProCharger on it. Now it slips going into 3rd gear. So if anybody with experience can help me out... do i rebuild my 65 again? or do i put a 4L80 in it? if 4L80, will they hold up stock? or do i have to do work to it? Ive heard that 4L80's rob a lot of power and cause trucks to not leave as hard. Any help on this topic would be much appreciated. Thanks guys!

 

A 4l80e will be great. I'm doing one slowly. With good clutches and setup for being dual fed, they can hold a ton of power.

Here is a nice post about this: (blackgmc knows his stuff, also see atomic )

https://www.performancetrucks.net/fo...9/#post4980146


They seem to steal a little bit of power, but the big issue I've read about is the taller first gear. Better rear end gearing and a higher stall can overcome this.

I wouldn't bother with a 4l6* and high HP in a heavy truck.

 

4l65 will hold some good power but a 4l80 is a better choice on a boosted truck..even in stock form they will take a dam good beating

 

Correct. I would prefer a 80e with a shift kit any day of the week. Much cheaper also then a built 65e.