looking to see if any of the crew can help me out! Thanks for looking by the way.

I have a 2002 GMC Sierra 4x4 with the 5.3 and a 4l60e behind it. The tranny is finally giving out on me and I have a lead with a 6.0 out of a 2003 HD truck that is a 2wd and has a 4l80e for 1800$ 210,000 miles. What would be the best avenue to go down to make this fit?

I have done endless searches to come up with a few answers and I want to make sure that this is right before I go ahead and pull the trigger.
I have heard that the rear output housing needs to be changed out along with the output shaft to get it to bolt up to the transfer case. Then a gear for the transfer case and then the driveshafts needs to be shortened and lengthened.

Thanks for looking and helping!!

 

you'd need a different output housing, a diff input shaft for your tcase, and then diff driveshafts.

 

Thanks for the reply!
Would you happen to know if the transfer case adapter that is between my 4l60e and my 246 transfer case would be a fit for the 4l80e to bolt up to. I'm thinking that they're both 6 bolt patterns.
Thanks

 

I have the tubular crossmember needed for the swap

 

You know there is a lube cup that has to be installed as well in the rear of case when converting from 2wd to 4wd...

 

ATRA guide states you can drill out the 2wd cup plug with a 1/8 bit and seal with a solid pop rivet.

I just bought a couple cup plugs without holes to try to convert my 2wd 4l80 to a 4wd 4l80. I'll post when I'm back from vacation and can try.

 

Thanks for the offer on the crossmember but that's one thing I'm good at. ( I just lied)

Yes I forgot about the oil hole for the swap. Thanks for reminding me.

Man that would be awesome to be able to see some pictures with your experience. Im going to do a write-up with my transfer because there is still some unanswered questions that I have. I would like to be able to help others.
Thanks for the help guys