Chris71694

Wouldn’t I have to go through and upgrade everything else if I did that or no?

_zebra

iTrader: (5)

not a bad idea to, but with a mild-enough cam, you don't necessarily HAVE to. you can even just to springs/pushrods with a bunch of decent cams & the smaller ones will still work with the stock converter (assuming you've got an auto like most other folks).

Chris71694

Yes it’s auto. So I found me a 5.3 with all its accessories including harness and computer. I can just pull my 4.8 out and drop in the 5.3 switch harnesses and the computer and I’d be good to go?

FFDP

iTrader: (2)

This is where you leaving out too many details.

What year and from what vehicle is the 5.3 coming from.

There is a big difference from parts used after 2002 model year, as in they won't be a direct swap other than the long block.


If the engine is from a 2000-2002 truck running drive by cable, the engine and computer would swap in. The harness is already the same so you don't have to change that. The computer won't just work though. You still have the security system that will prevent it from running because you swapped it into another truck. That would have to be either tuned out or get a security relearn done which may require a fancy scan tool because the computer isn't from the original vehicle.

Chris71694

Mine is drive by cable and from what I’m understanding from gm I can use any 5.3 from 99-06.... now if it’s drive by wire all I would have to do is use my throttle body... I’m also understanding that it’s all plug n play.

FFDP

iTrader: (2)

Nope, that is not exactly how it works.

The engine itself, just the engine. That will swap right in from 99-06.

99-02 use a completely different wiring harness for the engine and body compared to the drive by wire 2003-2007 model year trucks. The body harness, engine harness, fuse block, computer etc etc are all different on the 2003+ vehicles.


If you want a easy swap, find a 2001-2002 engine/computer. That will swap right in because it's already drive by cable. Then as I have already said, you will have to deal with the security system issue with the new computer.

Or have your factory computer re-calibrated/tuned for the 5.3 swap. This can be done cheap but it's going to be $100 type of cheap. Open your wallet if you want to get stuff done the right way.

Chris71694

So your saying that if I did a swap with a 5.3 that was drive by wire and just swapped my throttle body over, that I could NOT use my harness and computer? And just get my computer reprogrammed to that 5.3?

FFDP

iTrader: (2)

No, I said the engine swaps right in. You just can't use a drive by wire harness or computer.

You're previous post made it sound like you wanted to swap in a say for example a 2005 engine/harness/computer. That wouldn't fly because of the differences but if you just used the engine and your parts, then it would work.

Chris71694

I didn’t say anything about using a drive by wiring harness and a computer. I wanna use the harnes and computer that is already In my truck to go with the 5.3 in putting in!

FFDP

iTrader: (2)

Go for it.