907Ryan

So i am swapping my 01 silverado short bed 5.3/4l60E 4x4 to a 2004 GMC 2500hd 6.0/4L80E. I have got most of the engine/transmission questions and issues sorted. I am trying to figure out a couple of last minute things with the transfer case. I have both transfer cases from both trucks. I have read some things about different output shafts for the 4l60E and 4L80E. The 2001 was 4x4 push button auto. The 2005 Has push button 4hi-low but not the auto fuction. I guess my question is can i just use the Transfercase that was already mated up to the 4l80E with modifications to the transfercase support/driveshaft. Or do i need to swap some parts into the 4l80E (32 spline input shaft for the transfer case) and use the case from the 4l60E truck. I know that with the swap people have done it still shifts back the transfercase a like 1.5-2.5" and that required modifying/moving the mount. I already intend to by the cross member mount for the 4L80E transmission. Is there something similar i would need to get for the transfercase cross member or is it as simple as shifting it back. The forums on these get a little messy. I know ill need different drive shafts, shorter in back- longer in front. I had also read issues with the driveshaft/joints. The transfercase from the 4l80E is mated to an 8 lug read end and the joints are different than a rear end from a 1500, is that correct? Is that one of the reasons to swap output shafts in the transmission and us the 4l60E transfercase instead? Last, is there issues with the harness between the two transfer cases. I did by the harness adapter for the 4L60E swap to the 4l80E swap (this was before i knew you could move around pins and such). Are there similar things that will need to be done for the transfercase. Any information on this would be amazing.

you the man. sounds like a good plan

Sorry for the confusion. It is end goal but thats what i intend to do from the begining it wont be n/a again . Cross member from the 05 won't work, the frames are different. You may be able to modify it but at that point you might as well just modify your stock one - This is good to know. i have speed engineering headers so i will grab their cross member as well. It seems like i may just need to do the work and swap out the harness. it appears that would solve issues with the intake and the other items like the alt and ops. Thanks again for the quick replys. Its going to help a lot. The thing should be a monster when im done. I suppose one more question i have. For the 4l80E i want to do a higher stall like the 3000-3600 area. - the truck is getting a tsp stage 3 cam kit. I looked on summits website for the higher stall converter. When i search by truck it doesnt show any converters. When i search by 4l80E it shows many but with specific applications. Summit Racing SUM-700342 for example at the bottom says (For LS engines only using LS-1/LS-3 car type flexplate. Not for use on 1999-2000 LQ4 applications with +.400 in. long crankshaft. ). Now im pretty sure mine isn't a long crank being after 2000. And it should be a 6 bolt 11" pattern. im not home right now to look at the flex plate but i know there is a space difference. Would this work or would it require a spacer and long bolts to attach. I have been meaning to call a company and ask about it but if someone on here knows. I basically just want a replacement for the converter i have but higher stall. The tranny will get an upgraded cooler and a shift kit.

If i do the Whipple though i wont use the intake manifold. So would it just depend on the whipple/maggie. Unfortunately it doesnt look like either of them make on for the 01 cable driven and are all DBW. This means i will probably need to swap out the gas pedal and components. Unless i am missing something? luckily i kept the cross member off of the 05 for the 4l80E so im good there. I will have to find a shop up here that does driveshafts and let them make me one. Good to know about the ECU and harness, though i dont know if the throttle system on the 05 is attached the harness at all. If anyone else knows more about that swap some pointers would be much appreciated. I did plan on keeping the 6.0 injectors but i have also heard of them being a little light for boosted applications. Is there a recommended upgrade for them. For the items that dont work on the harness. By swap able do you mean i would have to incorporate them into the 01 harness? Thhanks for the reply!

I recently bought a 2005 2500HD. It has the lq4 and 4l80 in it which i have taken out. The project truck is a 2001 chevy silverado shortbed. I have removed the 5.3 and 4l60E out of it and im starting to put together a game plan for the 6.0. So far both of the engines are in my garage and i just need to know what else im missing. I know the 01 has a cable throttle and the 05 has a DWB throttle. Should I be taking the throttle system out of the 2005 and incorporating it into the 2001. Is that needed or necessary. Or could i just use the 2001 throttle and a different throttle body on the 6.0 The end goal is going to be a rebuilt 6.0/4l80E supercharged -most likely whipple. Is one option better than the other and what other complications might i run into. Another question is the harness. I have heard that the 01 harness will work with the 6.0 with a re-tune which its going to need anyways. Should i make the effort of switching over harnesses or just junk the 2005 ecu/harness. I know I will need the 4l80E cross member and some driveshaft modifications. If anyone has any suggestions there it would be much appreciated. The 2005 2500 was a extended cab long bed and the driveshaft is clearly longer than the one off of the 01 with the 4l60E. Is there a driveshaft i can get that will work in the shortbed/4l80E or will i need to get one custom to fit. I do have the new harness to switch over from the 4l60E to the 4l80E, i haven't looked into how that goes in but it should be plug and play with the 2001 harness. Im switching to electric fans and also got a harness for that. I have the transfer case for both. i would imagine i need to use the one from the 4l80E(2500), Is there any modifications or issues with putting that in the 01 Is there any other major items i will need from the donor truck.