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ok im sure someone already posted this and i just over looked it but i have a 03 z71 tahoe and im looking to do the 6.0 swap i have the 5.3 now what can i use off my motor and what will i need to get motor mounts tranny wire harness computer?? thanks for ur help if its been posted sorry just send a link please
 

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00Stormhoe
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You will want atleast a 01(or 02 dont remember)-up 6.0L. All your accessaries will bolt right up, harness and everything will plug right in but you will have to get your computer reprogrammed for the 6.0L and since its a different motor you need to have a case relearn done so the computer and engine are on the same page(so to speak). Your motor mounts and everything will work just fine the 6.0L will drop right in and bolt up right were the 5.3 sits. You will want to look into transmission work though, from my research just about everybody will tell you to do some tranny work. Good luck see you in 6.0L land once i can afford it for my tahoe.
 

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00Stormhoe
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If the trans is a 4l80e then i would do some resaerch on that swap since there is parts ou will need and modification of crossmember. If its a 4l65e then the trans will swap right in, you can bolt your trans up to it but you would want to add somethings to it just to help it hold the increase in power and torque.
 

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Personally, i wouldnt try and swap in an 80, but it all depends on how much work you want to put into it. it would be easier to just have your 60 built, imo.
 

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Personally, i wouldnt try and swap in an 80, but it all depends on how much work you want to put into it. it would be easier to just have your 60 built, imo.
That's true, but if you plan on really flogging it the 4L80 will hold up a lot better than the 4L60. Granted I'm sort of biased; I've blown up 7 or 8 4L60's, from stock to (supposedly) fully built.

I believe that you can move back the crossmember to support the 4L80, you would need an adapter for the stock wiring harness, and the VCM has to be modified to be able to control the transmission properly. Then there is the question of bolting to the stock transfer case; not sure what you would have to do there.

But as has been said here already, the 6.0 swap is fairly straightforward. I did it on my Avalanche, and it was done over a three day weekend.

Good luck. :) Should be fun.
 

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That's true, but if you plan on really flogging it the 4L80 will hold up a lot better than the 4L60. Granted I'm sort of biased; I've blown up 7 or 8 4L60's, from stock to (supposedly) fully built.

I believe that you can move back the crossmember to support the 4L80, you would need an adapter for the stock wiring harness, and the VCM has to be modified to be able to control the transmission properly. Then there is the question of bolting to the stock transfer case; not sure what you would have to do there.

But as has been said here already, the 6.0 swap is fairly straightforward. I did it on my Avalanche, and it was done over a three day weekend.

Good luck. :) Should be fun.
You have to modify the cross member because the 80e mount is 2 inches farther back. Then change the input on the transfer case, buy the wiring adapters, tune, lengthen front driveshaft, shorten rear driveshaft, modify the trans lines.
 

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You have to modify the cross member because the 80e mount is 2 inches farther back. Then change the input on the transfer case, buy the wiring adapters, tune, lengthen front driveshaft, shorten rear driveshaft, modify the trans lines.
Yikes. Is that only for the OBS or both the OBS and NBS? I knew that the mount was back a bit, but from what I have been told you can flip the crossmember or redrill a couple holes in the frame. I know that there is a transmission shop down south called PATC that makes a crossmember for the NBS trucks.

The wiring adapters are easy to come by, and the tune is doable too. The driveshaft stuff could be a PITA though.

Come to think about it, I don't know if it would be so easy on the OBS. The torsion bars go into the crossmember on them. I believe the NBS has coil springs in the front. Guess I'm sticking with the 60 then. :(
 

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Yikes. Is that only for the OBS or both the OBS and NBS? I knew that the mount was back a bit, but from what I have been told you can flip the crossmember or redrill a couple holes in the frame. I know that there is a transmission shop down south called PATC that makes a crossmember for the NBS trucks.

The wiring adapters are easy to come by, and the tune is doable too. The driveshaft stuff could be a PITA though.

Come to think about it, I don't know if it would be so easy on the OBS. The torsion bars go into the crossmember on them. I believe the NBS has coil springs in the front. Guess I'm sticking with the 60 then. :(
Both. Ive seen a alot of people just weld a flat plate on top of the cross member that extends back to drill the holes 2 inches farther back, then you just do some pieces to reinforce it.

Gotta take em somewhere and have them done.

The torsion bars go through teh trans crossmember on the nbs too. Unless you have a 2wd.
 

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Speed Holes
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Both. Ive seen a alot of people just weld a flat plate on top of the cross member that extends back to drill the holes 2 inches farther back, then you just do some pieces to reinforce it.

Gotta take em somewhere and have them done.

The torsion bars go through teh trans crossmember on the nbs too. Unless you have a 2wd.

OP has a Tahoe though, isn't that coil (like Avy)?


Hey George, I see you're in Fenton, MI, I've got a few buddies living there. Nice place, has that really expensive french sandwich shop, haha. I'm just about a half hour to the east of ya'.
I gotta ask, when you did your 6.0 swap did you have the use of a lift and or a cherry picker? I'm just wondering because I've got an LQ9 sitting in my barn right now waiting to go in possibly this winter or early next year, but I don't have much in the way of heavy equipment, other than a block and tackle hooked up to the ceiling of my barn, haha... :think:
 

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4l60s get a bad rep because we beat the piss out of them, and they were originally designed for, i believe, the tbi 350 which puts out a whopping 200hp. now my 5.3 has 315 and has the same trans. naturally i rod the piss out of mine and 25k later, my g80 and my trans are still fine.
 

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K2500's burbs (pry C2500's but have never checked) have leafs :wave:
In the front? for nbs?

edit: you mean rear. :guninmouth:
 

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HOT AIR BALLOON OWNER
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Look at glovebox codes... M30 = 4L60E.
 

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Missin the switches
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you have a 4l60e..

i just did this swap on my tahoe..your 4l60e will be fine..put a shift kit and a servo in it and be fine..unless you plan on really building up the motor, it will handle it just fine..i know of 2 people running supercharged tahoes with their stock 4l60e with the shift kit and they are holding up...

read my thread on the swap, as i just did it a month ago..

The hardest part is getting the bellhousing bolts, because the firewall sits out further on tahoes and crew cabs then it does on a reg or ext cab truck..other then that its all unbolt/rebolt and its in..PM me if you have any questions
 
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