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      2001-2004 LB7 to 2004.5-2005 LLY 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 LLY. This is the LLY underhood harness that has the LLY 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 LLY ECM. You do NOT have to send the LLY "on engine" harness (ie, the harness with the fuel injector connectors on it). You do NOT have to send the LLY 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 LLY conversion harness, you only have to send the LLY ECM.


      2. Can I retain my stock LB7 instrument cluster?

      ---Yes, you can keep your existing 2001-2002 or 2003-2004 LB7 instrument cluster. The 2004.5-2005 LLY custom harness and ECM is programmed to work properly with the older instrument clusters.


      3. Can I keep my 5-speed transmission?

      ---Yes, you can keep your existing LB7 transmission when swapping to a 2004.5-2005 LLY.


      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 do not have to run any wires (aside from optional DSP-5 switch) into the cab, the install is accomplished all under the hood just by plugging in the new custom harness.


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

      ---LLY ECM---LLY fuel injectors/fuel system/fuel pipes---LLY FICM---LLY heads---LLY on engine harness (the harness with the fuel injector connectors)---LLY underhood harness (the harness with the LLY ECM/TCM connectors on it). You can also just swap in a complete LLY engine if you wish. NOTE: if doing an 01-02 to LLY 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 LLY or 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.