been viewing this forum for a while and is very informative but cant seem to find out what I need to know

I have a 01 Silverado rcsb originally a five speed truck with a 4.3 motor...I bought the truck mainly for the shell with plans to swap, when I got it the five speed was out and a 700r4 with a floor shifter was in it, runs good and all but is extremely slow, no speedometer and shift 1-2 at like 2k rpm and takes forever to shift to overdrive I hate this combination...I want to get rid of all this crap but keep it an auto I don't mind the shifter as I have it mounted in my center console... question is if I keep it auto and install a complete 5.3 or 6.0 with a 4l60e or 80, will the v8 harness have plugs and everything I need to use that tranny and I will keep my floor shifter or what else would need to be done to get this completed? so main question would be whats needed to go from a 4.3 five speed to a 5.3 or 6.o auto?

any help would be much appreciated!!!

 

also would not mind keeping the truck manual but have read the 5speed trans will not hold up to any power upgrades...and cant find a way to get shifter to come up threw the cupholders in my 04 console without having a t56 6speed which sits back further, info on this will help also

 

If you plan to do a 5.3-6.0 swap go to psi and look at the swap wire harnesses.i got mine with ls1 and 80e wires with ev6 in injectors wired in. Cost under. 600 shipped. But if you want to use stock gauges call them up and let them know, john at psi pretty cool guy.
And the harness are a 4 wire hook up and grounds and starter wire and done very to to hook up its more pain in butte to run the wit like you because there so stiff

 

ill have to check it out...so does that mean I cant use a factory harness? and is a factory harness all one with engine and trans or are they separate? there are plenty engines and transmissions in my area and salvage yards that do good jobs of not hacking stuff up if I were to get a drop out

 

yeah you cAN use a factory harness.. but if you wana uuse a factory harness it be better to send it to someone that knows what there doing when seting up the harness for a engine swap. if you sent your harness out send the computer to them also it has to have VATS removed so it can run. the only reason i got psi harness was it looked cleaner then haveing a factory one anywas, my hasness is less then ha;f the size of stock one. you can use a factory harness but it be so work to get to work. nelson or psi help you and NELSON is over there >>>

 

PSI can set-up your harnes with any tranny you want to run also...

 

ok I was under the impression I could use a 99-02 factory harness and its going back in an 01 and then send my computer off to one of the guys. and it would save from buying another harness since I would have one but I will contact the guys and ask them about the computer tho

 

The harness's have minor differences between the years such as the pins for the charging system. It would help to know what the harness came from so you could use the correct calibration.

It's not a huge deal though especially if your having it modified because then they can add or delete options as needed to your harness and adjust the tune accordingly.

 

would it just be better to pull everything out of my truck? and what im asking is if I have a 01 5.3 with the engine transmission a complete harness and all accessories will I have everything I need besides sending the computer off.