LB7 to LBZ (Wiring)
- Thread starter RPM Motorsports
- Start date
Because then your stuck with a bunch of junk in your yard that nobody wants:roflmao:. I've bought a few salvage trucks for swaps, it's easier in the long run to tell the yards what I need and pick it all up at one stop. Plus saves a bunch of time/labor trying to cut through a junk truck to get what you need. And they all pretty much warrante the parts I buy, where buying a salvage truck you could get stuck with junk.
So I'm in the middle of doing this exact swap to my truck. I have an 03 LB7 and I'm putting in a lower mileage 06 LBZ with some goodies on it and I have a few questions:
Russ you mentioned this earlier in the thread:
Was just going over the wiring, and realized that one wire is missing! When installing the tap shifter.... You need to pull a wire (purple) from "B", and you also need to tap into the pink wire on the colum. If you don't, "M" will not illuminate on the cluster, and tap shift will not function.
Where does the pink wire on the column go to? We printed out a wiring diagram from GM from an 06 truck and the tap shifter control wire on the diagram goes straight to the TCM. Does tapping into the pink wire eliminate running a wire back to the TCM?
Why is is necessary to replace to the accelerator pedal with an LBZ pedal? Is it a communication issue with the ECM on the engine?
Last question, I'm using the fuse block from the LBZ. I know I don't have to repin two wires like i would if I was using the LB7 fuse block, but what parts of the rewire process at the beginning of this thread do I need to follow?
Russ you mentioned this earlier in the thread:
Was just going over the wiring, and realized that one wire is missing! When installing the tap shifter.... You need to pull a wire (purple) from "B", and you also need to tap into the pink wire on the colum. If you don't, "M" will not illuminate on the cluster, and tap shift will not function.
Where does the pink wire on the column go to? We printed out a wiring diagram from GM from an 06 truck and the tap shifter control wire on the diagram goes straight to the TCM. Does tapping into the pink wire eliminate running a wire back to the TCM?
Why is is necessary to replace to the accelerator pedal with an LBZ pedal? Is it a communication issue with the ECM on the engine?
Last question, I'm using the fuse block from the LBZ. I know I don't have to repin two wires like i would if I was using the LB7 fuse block, but what parts of the rewire process at the beginning of this thread do I need to follow?
Last edited:
Question on the C100 connector swaps - looking at both the LB7 (I have an 03), and the LBZ positions listed on the first post- I see what gets swapped where, but one doesn't make sense.
The first body side swap is for "C" (BN) to be moved to "N". On the LB7 and LBZ it shows "C" and "N" are both circuit 241 "Ignition 3 voltage" but the LBZ lists some additional qualifiers after Ignition 3 voltage.
If I swap this, it leaves the old "N" just hanging. Both are (BN) wires. "C" doesn't get used in the swap - so why are we swapping this wire as it appears to be the same circuit? I can see on the LBZ, C lists TP2 and N lists NP1, NP2 and NP8. Those qualifiers aren't on the LB7 that I can see. I used this link for the LB7:
http://www.duramaxdiesels.com/forum/showthread.php?t=13402&highlight=c201
The other is what happens to the wire that was "J", LB7 Engine On signal - I assume that not only isn't used on the LBZ, but just gets tucked away or cut/taped.
Any insight on the C to N swap and why as well as what happens to the old N wire is appreciated.
The first body side swap is for "C" (BN) to be moved to "N". On the LB7 and LBZ it shows "C" and "N" are both circuit 241 "Ignition 3 voltage" but the LBZ lists some additional qualifiers after Ignition 3 voltage.
If I swap this, it leaves the old "N" just hanging. Both are (BN) wires. "C" doesn't get used in the swap - so why are we swapping this wire as it appears to be the same circuit? I can see on the LBZ, C lists TP2 and N lists NP1, NP2 and NP8. Those qualifiers aren't on the LB7 that I can see. I used this link for the LB7:
http://www.duramaxdiesels.com/forum/showthread.php?t=13402&highlight=c201
The other is what happens to the wire that was "J", LB7 Engine On signal - I assume that not only isn't used on the LBZ, but just gets tucked away or cut/taped.
Any insight on the C to N swap and why as well as what happens to the old N wire is appreciated.
I had the same question,,, found out c and n get spliced together!!!
Just finished this swap also!!!
Just finished this swap also!!!
Found they get spliced together? So move C to N and splice N into C,(or C into N)? Why not just say remove "C" and splice it into N in all the instructions I've seen? Maybe the original "C" is the mandatory one to have connected and the N is nice to have?
Fun...
I'm looking at a similar issue but not sure if its related.
On my 03, the Shifter had a park switch that recognized with you were in Park - I'm assuming that is for starting interlock or something else? Is this something I need to address with the new shifter column,(LBZ), i.e. can I just tuck those wires away or do I need to connect them together or do something completely different?
Which pink wire do I tap into, on my steering column there is like 4-5 pinks, I went for the one the shifter plugs into on the column side of the plug, didn't work, and don't want to tap into 4 more wires to figure it out, but I am absolutely thrilled to have found this thread, there is no other information this good anywhere online. I am doing an lly to lbz swap, 2 of the 3 wires that you need to move were already in place on my lly, just adding wires right now, got the OBD II workin which is nice. Thanks for your time on this write up. It saved me tons and tons of time. I did the engine swap with the harness of course before doing any research into what all was needed to make it work right thinking that aslong as I have the lbz harnesses I'd be all set, can't believe there are so many little changes between 03-07. Makes a little more challenging but, as long as there is a will there is a way. I have an lbz donor truck so parts weren't a problem. Thanks again for the help!!
Down behind the brake petal, next to the E brake will be where you tap into to grab the keyed power. There is a black cover about 4”x4”, begins the cover there is a junction block. This thread saved me tons of time walking people through the swap, I just shoot them a link now .
On a funny note... did an LBZ conversion for a guy about 2 yrs ago. His tap shifter stopped working. He sent it to a “few trans shops”, and called this sites in house trans guru trying to figure out why. We were away racing for the season, so I couldn’t get to him. They replaced the tap shifter and “spent hours looking” for the issue. I told him it’s 4 wires, can’t be that hard... I was finally able to get him in.., he had an aftermarket alarm installed, & they completely removed that power wire for some reason .
On a funny note... did an LBZ conversion for a guy about 2 yrs ago. His tap shifter stopped working. He sent it to a “few trans shops”, and called this sites in house trans guru trying to figure out why. We were away racing for the season, so I couldn’t get to him. They replaced the tap shifter and “spent hours looking” for the issue. I told him it’s 4 wires, can’t be that hard... I was finally able to get him in.., he had an aftermarket alarm installed, & they completely removed that power wire for some reason .
Last edited:
Anyone happen to know what pink wire on the column harness your suppose to tap into as there’s like 5 pink wires
Which pink wire do you need to tap into as there are like 5 of them on the column harness
Anyone happen to know what pink wire is tapped into when adding the purple wire to B on the c100 connector ??
Those photos did mange to finally load at first I was getting a small square instead of seeing the photos . I’m still unclear to what pink wire was tapped into . I get one black wire has to go to b on the c100 the other goes to a pink . I put a lbz driveline in as well as the pedal cluster and steering column . From what I understood at first is if it’s already a lbz column all you would have to do is add one purple wire from B . But I’m obviously wrong .
Hi Team - This forum is GREAT. I've read through it E2E 3 times but still a little fuzzy. I could really use your help/direction -please!
I have a 2003 LB7 Silverado truck that had broken crank. I've installed a donor LBZ engine, 6 speed Allison, LBZ engine harness, LBZ ECM and TCM, and the LBZ Fuse/power distribution box. Had the VATS security disabled on the ECM. I updated the existing steering column with the new button shifter lever and the shifter indexer. I also installed the LBZ pedal and harness
I understand I need to update the LB7 C100 harness on the body side to match the LBZ. Luckily I also have the LBZ C100 connector and pigtail up to where it was cut off at the firewall on the donor truck. So I plan to use it, connect it to the LBZ C100 connector coming from the engine and splice it into the LB7 C100 body side wires. So I think I know what is needed to care for the additional wires for the button shifter and OBDII
But what else do I need to change? Do I still need to to update C2 harness/block and move the double orange wire from F4 to A8? Or is that not required in my situation since I'm using the harness, ECM, TCM, and fuse box from the LBZ?
I really appreciate any direction you can provide - PLEASE
Dave in Iowa
I have a 2003 LB7 Silverado truck that had broken crank. I've installed a donor LBZ engine, 6 speed Allison, LBZ engine harness, LBZ ECM and TCM, and the LBZ Fuse/power distribution box. Had the VATS security disabled on the ECM. I updated the existing steering column with the new button shifter lever and the shifter indexer. I also installed the LBZ pedal and harness
I understand I need to update the LB7 C100 harness on the body side to match the LBZ. Luckily I also have the LBZ C100 connector and pigtail up to where it was cut off at the firewall on the donor truck. So I plan to use it, connect it to the LBZ C100 connector coming from the engine and splice it into the LB7 C100 body side wires. So I think I know what is needed to care for the additional wires for the button shifter and OBDII
But what else do I need to change? Do I still need to to update C2 harness/block and move the double orange wire from F4 to A8? Or is that not required in my situation since I'm using the harness, ECM, TCM, and fuse box from the LBZ?
I really appreciate any direction you can provide - PLEASE
Dave in Iowa
I am swapping a lbz into a 2005 LLY chassis. I used the lbz engine harness, lbz trans harness. Lbz pedal and lbz shifter. Lbz fuse block. Lbz ecm , tcm. I already pinned the purple wire for tap shift in the c100 connector. The two ob2 wires in the c100 connector . Got the other wires ran for tap shift power ect. Only really question I have now is.. I see people are switching orange wire on the c2 connector for tcm power?" But what if I use the lbz fuse block and not the 05 llys? Do I still have to re pin the orange wire for tcm power?