Motor swap and transfer case.

[Gee713]

I have a 2005 sierra z71 4x4 and my current 5.3 is on its last breaths so im looking to either put another 5.3 or a 6.0. Ive never done a motor swap so the questions are never ending but my main concern is if i put a 6.0 would I need to swap to a stronger transmission which is the 4l80 I believe and would i need to swap my transfer case aswell? Any help and tips would help and would be Appreciated.

[Mikebtte]

4L80 is a good upgrade for any engine. The 4L60 is not bad but if you are going to be trying to put down a lot of power and want to beat it up the 4l80 is the winning transmission.

[davester]

I don't know if the 1500's with the 6.0 still got the NP261 "base" transfer case, but the 2500's and up (with the 6.0) got the NP261HD (slightly beefier),  I would expect you'll need to figure out how to rewire the truck for the 4l80e (may just be a harness swap), as well as work out how to reprogram the ecm/tcm to work with the new engine & transmission.

[Gee713]

Thank you guys. The truck is my work truck /daily so whichever motor i got i would put a slight bigger cam than stock and some headers i really just wanted some extra little power since it feels so sluggish. I dont plan to beat up the truck but a little fun here and there. Lol

[Gee713]

1 hour ago, davester said:

I don't know if the 1500's with the 6.0 still got the NP261 "base" transfer case, but the 2500's and up (with the 6.0) got the NP261HD (slightly beefier),  I would expect you'll need to figure out how to rewire the truck for the 4l80e (may just be a harness swap), as well as work out how to reprogram the ecm/tcm to work with the new engine & transmission.

So if i were to keep the 4l60 and just swapped to a 6.0 would i need that beefier transfer case or would my current one be fine or the transfer case would only need to be upgraded if i switch to the 4l80?

[davester]

14 minutes ago, Gee713 said:

So if i were to keep the 4l60 and just swapped to a 6.0 would i need that beefier transfer case or would my current one be fine or the transfer case would only need to be upgraded if i switch to the 4l80?

You are doing the swap to get more power on the truck, and you mention also putting in a bigger cam & headers (so even more power than a stock 6.0).  GM put the 4l80e behind the 6.0 to handle it's power.  I would expect problems down the road if you kept the 4l60e.  I wouldn't expect the transfer case to be a problem in 2wd, maybe if you use it hard in 4wd.

[CamGTP]

1st and 2nd gear are better in the 4L60e if we are talking off the line get up and go as well as just getting on it when under 50mph. Granted that is when the engine is not making 500+ hp because the 4L80e really needs some power behind it to not make it somewhat of a dog down low.

 

The 4L60e can be beefed up to handle a cammed 5.3 or 6.0 with some off the shelf parts during a rebuild, so that is an option too.

 

Then just don't forget about supporting parts for the cam swap like making sure fueling is there with a healthy pump and larger injectors to handle the power. Of course anything you do if it involves adding power or swapping to a larger engine/different transmission will require a tune.