01-04 LB7 to 06-07 LBZ harness FAQ's


LB7 to LBZ conversion harness frequently asked questions


1. What harnesses and computers do I have to send?

---For 2001-2002 LB7 conversion harness, you have to send the "ECM/TCM harness" from an LBZ. This is the LBZ underhood harness that has the LBZ ECM and TCM connectors on it, as well as the long tail that goes down to the transmission. You will also have to send the LBZ ECM. You do NOT have to send the LBZ "on engine" harness (ie, the harness with the fuel injector connectors on it). You do NOT have to send the LBZ TCM or glow plug control module. You do NOT have to send any LB7 harnesses. You do NOT have to send any body harnesses, fuse boxes, etc.

---For 2003-2004 LB7 to LBZ conversion harness, you only have to send the LBZ ECM.


2. If doing an LBZ swap, can I use the tap-shift and LBZ instrument cluster?

---For 2001-2002 LB7 to LBZ conversion, unfortunately the LBZ instrument cluster is not compatible at this time. You can still retain tap-shift if you wish (contact us for extra info), however you will not have a functional "6-5-4-3-2-1" display in the instrument cluster when in "M" tapshift mode.


---For 2003-2004 LB7 to LBZ conversion, yes, you can swap in an LBZ instrument cluster and have functional tap-shift and "M" mode display. The LBZ instrument cluster is plug and play into an 03-05 truck, however keep in mind your odometer mileage will NOT transfer over. To transfer the mileage over to the LBZ cluster, you will have to have the LBZ cluster reprogrammed.


3. Can I keep my 5-speed transmission?

---Unfortunately, no. You must also swap to a 6-speed Allison when doing the swap. The 5-speed transmission is not compatible with the 6-speed LBZ TCM, and the 5-speed TCM is not compatible with the LBZ ECM.


4. Can I use a variable vane turbo with this conversion harness/swap?

---Yes! The swap fully supports variable vane turbos. You do not have to use a VVT if you do not want to though.


5. Can I use EFILive DSP-5 tuning with this conversion harness/swap?

---Yes! Contact us for details regarding custom DSP-5 tuning.


6. Is it easy to install this conversion harness?

---Yes! The install is plug-and-play. You will also have to run several wires through the firewall and into the cab to the OBD port for the GMLAN data bus circuit. The proper pins are pre-crimped onto the wires, so all you have to do is insert the pins into the OBD port. No splicing, no crimping, etc.


7. What parts do I need to complete the LB7 to LBZ swap?

---LBZ ECM---LBZ TCM---Complete LBZ engine---Complete LBZ transmission---LBZ on engine harness (the harness with the fuel injector connectors)---LBZ underhood harness (the harness with the LBZ ECM/TCM connectors on it) NOTE: if doing an 01-02 LB7 to LBZ swap, you must transfer over your 01-02 oil pressure sensor.


8. Where do I send the harness?

---Contact us for shipping information BEFORE you send any harnesses. NOTE: The LBZ harness you are sending in must be stock, un-modified, un-cut, and fairly clean. If the harness is cut or modified in any way, there will be additional charge to repair it. Extremely dirty harnesses could also potentially have slight additional cost. Feel free to contact us with any questions regarding these policies.



9. How is the harness returned?

---The harness not only gets converted to run the newer engine, but the harness is also thoroughly disassembled, cleaned up, re-wrapped, and re-taped. We use only the best materials such as OEM automotive TXL wire, 3M Super 33+ electrical tape, German Tesa/Certoplast harness tape, OEM automotive grade high-temp nylon split-loom tubing, and genuine Delphi OEM pins and connectors. That way you get a harness back that looks clean and like new. NOTE: customer pays all shipping costs to and from us.

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